I make most meals from scratch and shop primarily from the refrigerated cases around the perimeter of the supermarket. I'm not a super freak about it, though. I will use convenience foods if I like them. I don't like many now, but I use dried pasta and have never made my own cheese. I did make some butter in a jar in Girl Scouts once.
Canned tomato sauce, tomatoes, beans, mushrooms, beets, soups, tuna, salmon, corned beef, some fruits, french-fried onions, refried beans are among the staples of my pantry. There's coconut milk and a jar of nopalitos in brine in there now. I buy the vast majority of mayonnaise, always Duke's, and yeast breads. I use canned whipped cream from the refrigerated case occasionally.
I also buy frozen vegetables regularly. They're not only convenient, but cheaper and/or better than what I can get fresh. I don't like the texture of frozen carrots or broccoli, but most frozen veggies are fine. I also buy commercially frozen fruit, shrimp, and puff pastry. I have Pepperidge Farm apple turnovers in the freezer now. I actually prefer good commercial ice cream to the denser homemade. Mrs. Smith's frozen fruit pies and cobblers are just fine to me, especially the blackberry.
My regular grocery doesn't offer much edible in the way of ready-to-heat frozen foods, but I have been known to buy cheese ravioli, stuffed flounder from a North Carolina company, Stouffer's mac and cheese is still good, breaded clam strips and frozen french fries and tater tots. I used to buy Stouffer's lasagna, but it went to the dogs a few years back. I like Deep brand frozen spinach and cheese samosas from my Indian grocer's freezer case.
I go crazy in the freezer cases when I rarely make it to Trader Joe's. They have not only edible, but delicious, frozen pizzas imported from Italy, cheese enchiladas, mushroom pastries with cream cheese flaky pastry, chocolate croissants, spanakopita, cheesecake and a whole lot more.
Now it sounds like I eat mostly convenience foods, which isn't true. I'm just sayin' not all convenience foods are anathema.