I didn’t read where any one said I can eat anything I want and not gain weight @jca. That used to be true, eons ago, but not in the last 30 years, when I started monitoring what I eat, to the point I rarely have to think about it (unless Rick brings peanut brittle into the house!!)
As @dammitjanetfromvegas said corn is a grain, like cereal or rice, not a vegetable.
You aren’t missing the point @Seek. People are going around in circles trying to explain themselves and making things far more complicated than they have to be.
Corn on the cob is about 100 calories, by itself which is not that much in the course of an entire meal. Put butter on it, and now it’s 200 calories. It’s that simple.
Unless, of course, it can’t be digested as @ARE_you_kidding_me claims, in which case corn has 0 calories. I know that much of it does pass through untouched. But some of it is harvested for the body to use as energy, but at the least you can lower the calorie count.