I think that the curve should exist. Some things people have to understand when creating video game costumes to real life, that some things are distorted. For example, you see an object, but they can only use so many poly's to make it look l round, and it can look off, by appearing to have distinct sides, whereas in real life, you would have to make it truly round, instead of squared off.
In this case, I feel the curve is a necessity for the sense of realism. Human hands are not flat, and I feel would requires a form fitting curve. Like was xes said, most of mapping on models are meant to create illusions, to make it look the way the programmers need it to look like, for example, the jetpack and helmet details on the 3d model of the darktrooper from star wars battlefront, they are nothing more then images/ drawings, which are wrapped onto the 3d model. Even from the MC model I have, those details are wrapped onto it, not actual poly's.