Powerlifting does not take as many calories as you'd think. In fact, lifting in general is surprisingly easy on the calorie requirement, so most powerlifters and bodybuilders incorporate cardio as part of their routine. You will burn a lot more calories by walking 10,000 steps a day for 1 month than you would doing an intense lifting session each day.

The reason you're probably thinking as to why lifters eat a huge amount is precisely because they're already large and muscular. Just 5% less bodyfat at the same weight results in roughly 200 more calories at maintenance for someone that is around 93kg.