>Also, say there simply aren't enough teenagers to make it reach an equilibrium point on price alone.
If there are scalpers, that means there are more people who want to come than seats available. If the price is, say, $50, then there's a certain number of people who would buy at $50. If that number of seats is made available, then the scalper incentive disappears.
>A sold out venue of trendy twenty-something's is can be worth much more than a handful of rich die hard fans willing to pay tenfold
I mean, if you want younger people, just make age restrictions. But you can have both by just getting a larger venue.
>Finally, it requires a really good handle on what that expected audience is going to be, not just what they can pay, which is hard to do.
Well that's where scalpers make the market more efficient, by having a lot of experience knowing what the expected audience will be.