eat one's broccoli
When someone puts up with something stupid just to get something good, they've eaten their broccoli.
My brother had to do 100 push-ups just to get a pizza. He ate his broccoli, and it was tough.
She had to listen to her boss's rants just to get a raise. She ate her broccoli, and it was loud.
He had to wear a hat for a month just to get a better job. He ate his broccoli, and it was silly.