Why did the ticket prices go up so much?

Why are promoters hiking their ticket prices up so much, and how much do the artists have a say in setting ticket prices? - NME asks after The Who announced they will charge 200 pounds for better tickets for their Wembley concert. Gideon Gottfried from Pollstar points out that artists rarely make money from albums any more with the rise of online streaming. Second thing he points out is production costs - some people expect a spectacular show when they come to a concert, which affects ticket prices as well. Since the 2015 terror attacks in Paris security has become a lot tighter, and that brings up costs, too.