For those who really don't cook, but want to save money, the trick is to learn which convenience foods are most worthwhile and learning to take advantage of sales.
This week, for instance, our third grocery store has catfish nuggets for $.99 a pound, a heat-and-eat food. Canned vegetables are 3 for $1. Fresh strawberries are $5 for 3 pounds. Large eggs are $.99 a dozen. And there are some deli items. If you're willing to boil eggs and cap and wash strawberries and heat vegetables, there's a good start on the week, from the store that's usually our most expensive.
Our main store has fresh strawberries for $1.25 a pound, premade salads for $2 a bag, a decent brand of frozen dinner for $1.18, all-beef hotdogs for $.99. Plus there are a lot of things that are normally a good deal.
Sandwiches can be a cheap convenience food. You can broil them, open-faced, in the oven for a change. Or toast the bread in a toaster. Buy a cheap pizza and add your own extra toppings.