My guess is that the majority are young 'uns who've more than likely had a few.
I have more than likely sung it in the past, younger days and had one or two too many but yes, most of the time I feel embarrassed.

The worst thing from our perspective though is that we are playing in the English league with Englishmen/women officiating.
I admit i am slightly cynical regarding officials in general "not favouring us" and this song does not help our cause in this regard.
If I were a linesman and I really could not be sure whether a player is offside or not, I've a good idea what my subconscious would be telling me to do!