> If you take in more calories than you need right now, your body will simply store them away for later, and you can eat a little less later on.

Given that it's a lot easier to overeat than to undereat in today's USA, the rest of chain proceeds as follows:

While you can eat a little less later on, you probably won't. Rather, due to eating while already full, your stomach will expand, and you will thereby overeat at subsequent meals (because food is plentiful). Eventually you will be at risk for health complications due to weight. An early death due to weight-related causes is surely a great waste of those extra calories.