I believe the “grow your own” suggestion is intended to be supplemental, rather than a fully developed subsistence farm in your back yard.

The beauty of growing your own is that you can decide what you want to grow! There are some things which are very easy and cheap to grow (such as fresh herbs) that are actually quite expensive and inconvenient to buy! Other things, such as potatoes, are very cheap in any grocery store (when purchased in bulk) such that growing your own is more of a hobby/curiosity than a budget saver.

Tomatoes happen to be one thing you can grow at home that are simply far more delicious than anything you can get at a store. Sometimes you might be able to get nice heirloom tomatoes at a store but they tend to be very expensive and usually seasonal.

If you get some experience growing tomatoes then you can produce a pretty large crop in a relatively small yard. With home water bath canning you can then outfit yourself with up to a year’s supply of home made pasta sauce (or even simply peeled and blanched tomatoes with basil leaf in the jar).

Valid concerns. I won't ignore the orphan crushing machine and every situation is different, but a lot of food can be grown in an apartment.

I had a 300sqft bachelor pad in Vancouver where I managed to grow tomatoes, goji berries, greens and ALL the herbs. I kept my herbs in pots under a full spectrum light indoors, clipping and drying as they grew out. After set-up I only had to water, fertilize sometimes, and prune as needed. Greens, I kept harvesting young and re-seeding. Aside from watering, it took almost no effort to put a significant dent in my grocery bill.

Now, I have a 4x8ft fenced garden in a shared yard where I grow so much I barely buy produce in the summer. Aside from weeding, sprouting and transplanting in the spring, the main labour is watering, which only takes like five minutes. I get my seeds from things I eat or the public library seed share, so those are free, too.

I legit grew three pumpkins, four ziplock bags of sunflower seeds, beets, snap peas, opium poppies, carrots, tomatoes, gooseberries, strawberries and still have a herb shelf inside.

I get that's still not a year's worth a food, but it's a lot for tiny bit of dirt, considering I knew nothing about gardening before.

Oh but get GMO pumpkin seeds. White mildew rot is a pain in the ass and everywhere. And a dehydrator if you don't know how to deal with lots of food at once, you can make chips and crackers out of anything.

I'm pretty lucky in that my friends hunt, too, so I get a butt load of deer meat every fall.

Land available isn't true at all. A sunny windowsill could provide a family with herbs, leafy greens or something like tomatoes. Check out the kratky method for a pretty cheap introduction to hydroponics

Not going to be anywhere near enough food for one person unless you have more land available for yourself than people in a city or even most modern suburban developments are likely to have.

i did a study on area needed for food production a while ago, and IIRC

• per person, about 1000 m² are needed to feed them. depends a bit on where you live though
• fertile land produces around 3.5 t of grains /ha on average. with modern technology, the peak is 7.5 t/ha
• by far the most area is needed to grow calorie-heavy foods. like, you could get far with 30 m² for yourself if you only plant vegetables and buy the grains at the supermarket
• grains are really cheap, compared to vegetables. that's because vegetables are labor-intensive (difficult to automate because they're often fragile and sensitive) while grains can be automated on ultra-large-scale farms with farming machines, so they're really cheap.

Note: 1 t = 1000 kg, grains = cereals

All I can guess is our farmers haven't been given any initiative to sell to a middle man (store) that marks up. In essence, a farmer's market is supposed to be like going directly to the manufacturer and telling the retailer to fuck off. The farmer is happy, I'm happy, it works.

If your farmer's markets are expensive, I'm guessing it may be novelty or hobbiest produce out to make a quick buck of a trend.