They're also more emotionally taxing to create, and come with several externalities that aren't baked in to the price of the dollar menu:

  * dish washing (do they even have dishes?)
  * power usage of stove
  * time to clean up
  * a singular, large lump of time to go out and buy all those food
  * the necessary mental spoons to plan those numerous meals each week
  * a refridgerator that works (mine is currently broken, for example)
  * a willingness to accept the cost of losing a lot of food when the fridge inevitably breaks

And so on

  * a refridgerator that works (mine is currently broken, for example)

Other than eggs, and this is in the US not all countries, you don't need a refrigerator for the listed items. Beans, rice, and oats do not require refrigeration. Many fruits and vegetables also don't need refrigeration [0].

  * a willingness to accept the cost of losing a lot of food when the fridge inevitably breaks

This is mitigated by learning what does and does not need to be refrigerated and storing things properly.

[0] https://extension.purdue.edu/foodlink/includes/pubs/Storing%...