They must be one of those people who can eat a McDonalds double quarter pounder + fries (1000 calories) and be good for the day.

They'd be horrified how many of those combos I could eat in an hour while easily enjoying it.

Add a large coke and you can easily hit 1500 in one meal. 1 lunch, 1 dinner, a snack, and a nice healthy breakfast and you can easily clear 4000-5000 a day without feeling like you ate an abnormal amount.

I don’t know what gp implied but I know that in my personal case, I’m way less hungry after physical effort. So I wouldn’t think he talked about calories but more about the ability to eat.