Quote Saint Simon="Saint Simon"every idiot who never goes to league matches will be there and will have been drinking all day, it'll be a miracle if its observed'"
Exactly. 80,000 people at Old Trafford, it's fair to say that if just the regular fans who attend Knowsley Road and the DW attended that it would be nowhere near that figure, fans of other teams or not. It is also safe to assume that 3 o'clock kick off on a Sunday afternoon at either place and the silence would be served impeccably.
Therefore, if idiots decide to outwardly show their lack of dignity, they should be ignored (or preferably thrown out of the ground and banned from finals for the rest of their lives, seeing as that is probably the only game they attend)