I don't know if some people really do this "wasting" on purpose or not (observing human life would suggest that, statistically, some do) but my opinion would be that if you sign up to play a 30 minutes game, you have to be prepared to sit at the board for an hour. If your opponent chooses to spend the majority of their own time doing nothing, then it is you who will benefit ultimately.
It might be boring but if you want faster play, use faster time controls. There isn't really anyway to "force" someone to play the way you want them to.
I won't hide my dissappointment but lately I have been meeting awfully crappy players. I like to play online chess with 30 minutes time interval.
Though lately I've been meeting opponents who seem to sleep (play no moves) for most of the match & start playing after an awful long time. It is mostly wste of time for the opponent.
I would requet you to share your views on how to del with these time wasters without losing points?