I can't remember the numbers, but Spurs have that "Bottoms Up" beer dispensing system. The beer cup is basically sealed using a piece of metal with a magnet that clips into place at the bottom of the glass (which has metal around the hole). These pieces of metal can be keepsakes (e.g. sponsors, or other guff) and cost buttons when bought at volume. I assume the plastic cups are re-useable.
According to AI (disclaimer) - the Spurs stadium can dispense 10,000 pints per minute at capacity.
They sell around 65k pints per match.
Revenue from beer is around £330k per match.
Knowing our fanbase, we could and should be doing better than we are - but as mentioned the bogs are under-capacity. Perhaps they could install pissoirs around the bar area.