I feel like there is too many people camping things; camping key respawns, camping shiny stone respawns, etc, etc. It takes fun out of the game, at least for me.
I've played certain MMOs, not saying that Glitch is an MMO, that have logged me out of the game world if my character didn't move within a certain amount of time. It's fair to the other players who don't see 'dead characters' just littered all over the world.
I think it'd be a great addition to Glitch. I'm sure some people would find a way around it, but I think it'd catch some of the lazier campers, and that would be plenty of good for the game.