It's great fun though! Dunno if it's the same with everybody that does it, but we've got a rule for each bar. For example there's the dice pub, you roll one dice and whatever number you land, you've got to finish your pint in that many goes. Another is the silent pub, where you can't speak until you've knocked back your pint, failure to do so results in a penalty shot, generally the strongest spirit behind the bar.