Don't forget about the musicians' pay!
I don't see any reason why, especially young generations, should need monetary privilege to enjoy classical music.
The same for the London Philharmonic Orchestra, which is a registered charity.
At least in Europe, the cheapest tickets being around that price is typical.
Sometimes it's a lot cheaper -- I saw an opera in Vienna for 3EUR, and a youth orchestra (presumably a skilled one, given the venue) playing in Paris tomorrow is free!