I like to watch Northampton Saints (Rugby) and before our ground was extended we had to hold the premiership matches at MK Dons stadium. The stadium was built for football and didn't have drinking facilities, so picture the first couple of rugby premiership matches there.
The bars were overrun, so much so that the staff just stepped back and let the fans serve themselves with "honesty boxes" on the bars! It worked, and I suspect they took more money from the rugby fans just dropping notes onto the bar and rushing to get back to the second half than fuzz with change.
By the third game the venue had caught up, and had pop-up bars all over the place so you didn't end up missing half the game queuing for half time drinks.
What I also love about rugby, is the players join you in the bar after a game and enjoy a drink and are pure gentlemen.