Tribute Acts

I was with friends at the la marina sports complex to watch a tribute to Gene Pitney and Roy Orbison . But was thinking are the promoters missing a trick by not getting in younger acts like Rod Stewart, Elton John ,Whitney Houston, and the like .I am in my fifties and there must be many more people of my age and younger who work or have property here with money to spend . where do they for a meal a drink and dance. Just a thought? .