Each player is allowed 90 seconds to make their next shot. That means you are, too.
Each player SHOULD be allowed those 90 seconds, without you commenting on their pace of play.
Should you find yourself playing with someone who does not play as fast as you like, simply don't play the game with them again.
As for me, there are a number of things one can do on the machine while waiting... forums, solitaire, television, surf the 'net, chat.
It's not a race.