I rarely have leftover fabric and if I do, it's a small amount. I don't save 1 or 2 little scraps, but if I have something like an uncut half yard, I'll fold it and save it just in case.
As for food, I live alone, so I always have leftovers. I don't eat them past the 3rd day, though. And I'm a HUGE doggie bag take homer person. I'll eat out and get at least 2 nice meals, sometimes 3.
I've worked my butt off supporting myself for many years, and I'm quite frugal. Yet if I want something 'pretty', yep, I'll buy it. I measure and plan, though, and only buy what I need. I don't hesitate to spend money on nice things but only buy what I'll use.