First job in a small school (third year teaching) I didn't do it first game - went to large HS, first taught in large HS, never even knew such a thing existed). Huge uproar, but being young and stubborn I didn't back down. Eventually got to where it was mostly accepted, and many times applauded as we were in the stands in some critical game third quarters. Had one dad that pushed hard a few years later tell me the band pretty much won a playoff game where we were behind at halftime (first time all year). We played a ton in the 3rd quarter, and went on the win easily.
Next small school I went to I decided I wasn't going to fight it. By the end of the second year I had two instances where kids were given spiked drinks (one ended up in the hospital), and one lasting image of a kid in a band uniform in cuffs being put into a police car because he got in a fight (he was jumped) in addition to some other incidents. Told principal I was done with it, and before I had finished my first sentence they told me they agreed and to send anyone that questioned it to them.
Bottom line, I hate it. However, depending on the community I would put this in the category of 'pick your battles.'
I am curious how many of you allow your students to take off during the 3rd quarter of the game after halftime and return before 4th quarter, and how many do not? Curious about your reasoning either way and if you do, do you use it as an incentive for students during the week or what?