Okay, as just a random customer it's none of my business, but it struck me as odd at a recent best festival that most beers were priced around 90p, 100p or 110p for a half, except for a few high-% ones.
Assuming pretty much all of it will get sold, wouldn't it be a lot easier to just call all the "normal" beers a quid, and save the counting out of 10p change each time, then counting it back in after the next half?
Lots of good beer, though.