Nobody has to throw beer in the air, any more than they have to throw tea, coke/pepsi, bovril, water or whatever pie they happen to have in their hand when we score.if nobody owned trousers then nobody would shit their pants..... taking beer in to stand was predictably going to end up with some thrown in the air and some plastic cups being thrown around.
People who do it are twats, regardless of whether they get no punishment or they get their goolies sanded off.