If the product of a cultural institution, be it art, music or drama, were truly in demand, then it would be marketable and the institution would be self-sustaining. There should be no problem in charging admissions. I do not recall a free museum in Europe.
Many local "bar bands" have been in existence for years if not decades. Their art is in demand and therefore profitable. Establishments hire them to draw customers, who pay through a cover charge or higher prices. All benefit -- the customer enjoys and the establishment and band profit. Why can't the cultural institutions follow this model?
Dale J. Placey