Having a tiny fridge might work for small households in walkable cities who have plenty of time for multiple shopping trips per week, but for many of us, it's out of the question.
Although changing our shopping and eating habits can be an important part of a healthier lifestyle, and is crucial for lowering our environmental footprint, there are some constraints that can limit those changes, such as our finances, our household size and demographic, and the neighborhood that we live in. And while I tend to agree with Lloyd that "good cities make small fridges" (and to disagree that small fridges make good cities), I think it's kind of putting the cart ahead of the horse, in the sense that until the necessary infrastructure is in place, both public and private, urging people to shop more frequently and to store less food on hand is not a viable solution.
Even in an extremely walkable city that may have good grocery stores and farmers markets, and which is most likely to be more expensive to live in, having the time and money necessary to go shopping every other day is still something of a luxury, and isn't an option for the rest of us. And the practice of 'just-in-time' shopping could very well leave us in a pickle if our income is reduced or an emergency happens, in which case we might be wishing we had put more thought into our food buying habits.
Small fridges might work if going to the grocery store several times per week is an option, but for many busy people, it's not the best solution. And multiple trips to the store can also yield higher grocery bills, because of the dangers of impulse buys, the tendency to add food to the cart because you're hungry, and the additional expense of both time and money that shopping frequently requires. There is some evidence that bigger fridges can "encourage unhealthy eating habits," but if those fridges are filled with good wholesome foods, and not bulk ice cream from CostCo, that insight doesn't seem nearly as relevant.
For singles, couples, and empty-nesters, food shopping and preparing is an order of magnitude easier than for families with kids, especially those who work several jobs and are always pinching pennies, and those who live in so-called food deserts, the suburbs, peri-urban areas, and rural locations. Between job and school schedules, music lessons, sports practice, and all of the other daily and weekly family commitments, and the long distance that some people have to travel to the store, it's hard enough to get to the grocery store and farmers market once a week to buy everything we need (not to mention the challenge of doing that shopping with uncooperative kids in tow), and to do so without going over our budgets.
Feeding a family, and doing so affordably and seasonally, can be challenging on its own. And feeding them with nutritious foods while sticking to a budget (as well as dealing with picky eaters) is a whole other ball game. But with the right pieces in place at home, parents can enable healthy meals and weather shortages of cash, while also preparing for emergencies. It does take a little (or a lot) more planning and prep time, but the security of knowing your family has food in the pantry or fridge or freezer is worth a heckuva lot more than that time commitment, in my opinion.
Bigger fridges, freezers, and pantries can support bulk buying, which not only reduces the amount of packaging per serving, but also helps save money over the long run. Buying in bulk, which does require a little more cash upfront, and a little more planning in terms of storage space, also allows for families to always have their staples on hand, and then makes it much easier to cook from scratch, which many families do daily. During peak harvest periods, it's also possible to buy boxes or bushels of 'seconds' (blemished) of fruit or veggies at a big discount, and although they require some preparation for storage or eating, the cost reduction can be significant for those on a tight budget.
Having a larger refrigerated storage option, whether that's a freezer or a fridge, also enables families to buy more seasonally for peak ripeness and nutrition, and while non-refrigerated storage -- such as canning -- is good for some things, there's the case to be made that freezing certain foods is far better nutritionally (and taste-wise). And freezing, although it comes at a higher energy cost, is much simpler, quicker, and more accessible for the average person, while canning has its own considerable learning curve and time investment. I've got nothing against canning, having grown up eating a lot of canned food that my mother put up, and I think that both freezing and canning are viable options for eating better year-round, and for helping to keep food budgets under control.
A freezer, especially if it's an efficient chest-style freezer, can be a great asset for those who want to prepare for the week or season ahead by freezing both ingredients and full meals, which can then make meal preparation much easier on busy days. A chest freezer takes up some space in the home, but can often be placed in a more out-of-the-way location than the fridge, and because of their design, and the fact that they don't get opened a bazillion times per day, are quite efficient.
A large fridge, or even a spare one, can be put to work storing some of the fresh produce from weekly farmers market trips, neighborhood fruit foraging, and garden harvests. We often find ourselves wanting a second fridge, just to store fruit and veggies, as right now a third of our fridge space is dedicated to storing apples from the neighbor's trees, which would otherwise rot before we ate them if left at room temperature (or we might just go crazy from the ever-present cloud of fruit flies).
A dehydrator is another great tool for making the most of seasonal food, but most consumer-grade dehydrators have the same problem that the freezers in fridges do, in that they aren't meant for large batches of food. We've got a countertop dehydrator model with extra trays on it (which is currently being used to dry some of those apples for the winter), and it's great for small batches of food that will eventually be stored in glass jars in the pantry, but it's not up to the task of processing a whole bushel's worth of fruit in one or two batches, so I can see a large DIY solar dehydrator in our future.
Having enough pantry space for non-perishables is another key element of a well-prepared family home, as it allows for the storage of bulk-buy items, and they can often be outfitted with free or low-cost storage containers. Food-grade 5-gallon plastic buckets can often be had for free from institutional kitchens (schools, universities, corporate campuses, etc.), and they only require a good washing to make them ready to store large quantities of beans, grains, and other staples (a 25-pound bag of grains or beans will fit into a single bucket). Glass jars are also relatively easy to acquire in many locations, whether you have to buy them new, find them at a thrift store or garage sale, or pick them up from behind a bakery, deli, or restaurant. Both of those storage options are also rodent- and insect-proof (other than the fairly common grain moths that can hatch from eggs already present when purchased).
There are definitely benefits as well as trade-offs when it comes to both options -- living in a leaner manner, such as with a small fridge/freezer and more frequent shopping, and in putting more long-term planning into food buying, preparation, and storage -- and the best choice for some is often unworkable for others. For those of you who live in walkable cities with easy access to farmers markets, grocery stores, bakeries, and butchers, and who can live just fine with a little fridge, it's a great option. For those of us with larger families and fewer choices for shopping, and for the time-stressed and uber-frugal, having a large fridge, freezer, and pantry can be the better choice, as it allows us to take better advantage of seasonal foods and sale items, as well as offer a bit of food security and help to support better year-round nutrition on a budget.