> it's quite possible to eat fast-casual for the same price of many of these kits (especially if you live in a suburb where restaurants tend to be much cheaper than in e.g. SF)

Sure, but now we're not making an apples-to-apples comparison anymore, given the quality of fast-casual food vs even nominally home-cooked food. I don't like fast-casual food, and I don't think I'm alone in this. I enjoy home-cooked food and I enjoy food from restaurants above a certain quality bar.

What you're saying isn't that far off from saying "why does anyone cook _or_ go to restaurants when they could just have Soylent?". Quality matters to people.