BUTTTT, this is the same with British cuisine here. Often people buy a pasta bake sauce, shepherd's pie seasoning mix, fish pie mix, etc. People can choose to use real ingredients in either country. We just tend to choose convenience. 
Actually, I completely dismiss those things because they're not familiar to me (and the few convenience things I've tried just don't taste good to me)... but you're absolutely right. There are a LOT of convenience foods and ready meals here, too. They're just not the ones I'm used to.
I'm sad about the lack of tuna noodle casserole the way my mom made it (Campbell's
condensed cream of mushroom soup, tinned green beans (the US kind that have added salt in them), egg noodles, and tuna... cook the noodles, mix all the ingredients together, put it in a casserole dish and bake 'til the top dries out and gets bit of a skin on, about 20-30 minutes at 350F... *sigh* I want that so bad...)