[GameMaster]

Its up to the user to 'play responsibility' in terms of time management. Very few do and its admittedly hard. But imposing time limits for paying customers is crossing the line, IMO.

The best analogy I can think of is tobacco companies limiting the amount of cigarettes one can have per day. Which sounds stupid but I believe its a similar scenario.

If the game is offered free though, by all means, restrict whatever you want.