I eat the same thing every day when I wake up (if I eat) yet if someone was feeding me the same thing for dinner for months at a time I'd definitely lose my shit.
I have two different breakfasts that I alternate, but they can be a little different every day. But they are huge breakfasts, so I don't feel hungry for about 7 hours at least. Yeah the same dinner everyday would make me crazy, too. I wonder why it is like that

Maybe because in the morning after sleeping we mostly need energy (carbs) so our body is hungry and doesn't care what you eat, you don't have the energy to complain

While in the evening, after a long day and probably other meals/snacks in between, added to the fact that we need all our protein, fat and all micronutriments intake, our body craves diversity.