Even if someone is aiming for maximum muscularity naturally, they really cannot get that big. The waist in and of it's self requires years of ab work to gain an inch or two. Most powerlifters want to put up the highest numbers they can whether they're natural or not and don't really care about body fat percentages, so they look unappealing. But once a powerlifters cuts, they look better than most worried about aesthetics.
Personally I want to look good and have low body fat and do powerlifting, I know my numbers would suffer, ill be in a lower weight class. It's all a matter of what you want and care about...