> - Some people just don’t like to eat that much. They don’t actually have a faster metabolism. Eating is just a chore to them so they rarely do it.

I had two friends exactly like this. One of them was 6' and 135lbs when he started college. Another was 5'5" and under 120lbs. They both said that growing up they thought food was gross and only ate because it was the only way not to be hungry all the time. They both started enjoying food in college and gained a bunch of weight. The one who is 5'5" topped out over 200lbs and now weighs around 180. The other I lost track of, but he was on the same trajectory, gaining 30lbs during our undergrad years.

Your first thought might be that they grew up poor, or that their parents didn't have tasty food around the house, but they were both middle-class, and there were lots of regular foods like pizza and burgers that they disliked as kids and ended up enjoying to excess as adults.