Depends on weight and speed, of course. According to the standard calculators floating around, a 200 lb (91 kg) person running a 10k in an hour is burning about 960 calories per hour. And that's a casual/comfortable pace for runners.

People aren't gonna be able to get off the couch and suddenly be able to burn 1000 calories per hour, but that's probably a pace within reach for most people within a few months of training.

There are easier ways to control weight, but for people who enjoy running, those calories give a lot of flexibility in how to eat.