My guess: Empty seats look bad and and pricing fans out of concerts may hurt fan relations, even losing them completely. Also concerts are mainly for the artis

My guess: Empty seats look bad and and pricing fans out of concerts may hurt fan relations, even losing them completely. Also concerts are mainly for the artist to make money. Traditionally they're getting fucked by record labels, making very little on sales of media. Concerts is when you're actually getting paid. It thus being a somewhat less corporate process to decide ticket prices can mean that they just charge as much as they need and want, not as much as they can. Artists are generally considered to be a polar opposite to the "short-term-profit-maximizing" crowd.