That's all? That will stop literally nobody if their intention is to leech off of other players. As the original poster said, the person (whose name was edited out of the post, meaning everyone else will get the joy of being caught unaware) would tap the controller every now and then, preventing them from being kicked. On console, simply placing your remote on the floor in a position where the right stick is being tilted would prevent that, and on PC, I'm sure there's billions of ways to get around that sort of AFK Kick system. I'm still fully in support of a 'Vote to Kick' function, to get rid of these types of players, since it seems that the devs are against making private sessions.