My son goes to college fairly close, 1 1/2 hours away, so we try to go to at least one of his concerts each year. His school is not known for music. We have to pay $15 each to get in for a (IMO) very bad concert.
I was pretty shocked the first time I went since I went to a school that was known for it's music program. While they do wear tuxes etc., I feel like I'm at a rehearsal because it's very informal. They start with the best group and the evening goes downhill from there so those students can leave when they're done. After the first year, we wised up and we leave after his group, so now we pay $15 a piece (plus parking!) to attend a concert for about 20 minutes and then meet him for coffee.
At my old school, the only concert that they charge for is the Christmas program and it is a production that is choreographed to a t and very well rehearsed. For that concert they charge almost that much and it's well worth it. On other performances, they generally make their money on the CD's people buy of the performances.