I don't think "overpriced" is a valid criticism of a system built to funnel money from people with disposable income to artists. It seems to reflect a distaste for the entire concept of arts patronage.
Other things that are overpriced to a pure pragmatist: getting your name in the credits of a video by a youtube creator you'd like to support. Tickets to a recital for a recent graduate raising money to travel during audition season. Getting a museum wing named after you. Appointing a poet laureate.
If you want to live in a world where artists can afford to devote a majority of their time to their art instead of day jobs, you have to tolerate that systems are built to fund them, even if you balk at some of the most sensational price tags or artists' tastes.