This has always bothered me about Glitch. I don't eat in secondlife. I can only assume its because other games (which I don't play) were designed with eating/energy mechanics so they just designed this game with the same "in the box" style of thinking.
I get no pleasure from eating in a game. Cooking is only mildly interesting, the recipes aren't particularly creative or something I'd want to try at home.
I do get some real satisfaction/relaxation from meditating, and I get a weird sort of satisfaction from the mining grind but that is because really swinging a pick at a rock would be backbreaking but doing it on a video screen is easy. Eating on a video screen is stupid and not at all satisfying like real eating would be.
I suspect that we eat for energy in glitch for no better reason than that other games were designed this way,