This makes absolutely no sense to me. If I was in the wild and needed to find food to survive, the last thing that is going to help me last till my next meal is stealing from my muscles. I need those to hunt / search for food with. What good is lasting until I find a meal if I'm so weak that I can't catch it? It just seems evolutionarily backwards. Why would we evolve a survival mechanism that doesn't help us survive? I suppose the fact that humans are one of the only land based mammals to have our fat deposits as a layer under our skin may have something to do with it. Most animals store fat inside their bodies around their organs. We have a blubber-like layer under our epidermis like whales do. Why? Nobody knows.
Now, I can't speak for all gamers, but when I really get into a game I forget about bodily needs and functions. I have gone as many as 9 hours without eating, drinking or... excreting without realizing how much time has gone by. I can remember entire weeks going by with almost no food, eating maybe only twice in 24 hours when truly EPIC games came out. And I'm not even a REALLY hardcore gamer. I'm sure there are those who have done far, far worse. Surviving on energy drinks, candy bars and chips for extended periods of time without sleep. Need I remind us all of the rare game related death stories?
My point is, if our bodies worked the way evolution intended them too, gamers should look like Greek gods / goddesses, including the pasty marble complexion (lol) but minus some of the musculature. Granted, we wouldn't be buff, but we would be lean. Why doesn't it work that way? If scientists could work out a way to make our bodies feed off our fat instead of our muscles first, the obesity epidemic would be cured.