I'm with TB on this. Sports events often surprise me. I'll be sitting in a pub, reading quietly with a coke or tea, and over 20 minutes everything will get louder, busier and all-together unpleasant. I don't keep up with the events so my calender is never marked.
If I AM somehow aware of a football game beforehand, I make a point to stay in. Loathe it all and the attitude it provokes in many of the supporters. This is by no means ALL of them, but the large sub-section who take it as an excuse to get drunk, belligerent and tribal ruin any fun that might be picked up by osmosis from the REST of the crowd for me. Easier to stay in and be quietly annoyed about having the option to go out somewhat taken out of my hands.