Non-trivial spending includes expensive mandatory expenses, like rent/mortage, insurance, maintenance, etc.) Spending $20 on a lunch once a week (if that's what I wanted to do) is trivial, both in cost and importance.

Obviously trivial expenses are the first to be optimized away when a budget crunch occurs, because they are also trivial to remove/stop. It's hard to delay rent or a car payment withour real consequences, but there's no real consequence to not eating out lunch anymore.

I interpreted "trivial" as negligible, too small to cut from the budget, even in a crunch. I see you're using a different definition. However, I also think that $40k per year is a perpetual budget crunch, so not really a crunch at all.