Because being a football fan rather than just a spectator means you are involved. You get the lows but you also get the highs, and even though the low points (like today) make you wonder why you bother, the highs when they come are some of the best feelings ever. You participate by being there. You can't be a Manchester United fan just watching on the TV, but you can be an Altrincham fan because you were there. And when you go into work/school/college the next day and all the plastic United fans are raving about the latest game they saw in TV, you know that you were out in the pissing rain, freezing your bollocks off just for the hope of, and the moment of enjoyment of, a hard fought win. You get the smug satisfaction that you actually support your team though thick and thin, and that makes you far suprerior to the United shirt wearing plastic fan.