To first point. Bit more complicated imo. The venue would have to tier pricing (which many do via vip) to not exclude the m people who won't pay $100. But does require more effort on venue part.
It's not a symptom. It's necessary to have those lower prices to keep your image and your fans and impacts your long-term earnings, and so we're back to scalpers being nothing more than parasites and a net loss.
It's the same thing with the shoes, if they prices the shoes at their 'true' value, they alienate their customer base and the shoes lose value. The scalpers are actively harming the market.
The artists/bookers/venues choose ticket price levels based on a number of factors. They want to fill the venue and be profitable, but they also want to maintain a relationship with fans, which is going to get soured if the fans feel ripped off. There is also the factor of drinks sales, if you pay a ton for the ticket, you'll probably buy fewer drinks, and venues make a lot of money on drinks.
If they priced the tickets as high as the market could possibly bear, only the people with enough disposable income could go. That makes all of the fans who cannot afford the tickets angry that they cannot go, you really don't want to do that if you want to maintain a fan base.
Scalping is illegal in many countries for good reason. Here in Denmark, you can resell tickets all you like, but only at or below face value. It works and the artists/venues get to set the prices at levels that match their fan bases. Scalpers who don't care about the bands, but only about profit, don't get a say, because they they shouldn't have one.
Which is why we have people who are experts in marketing and economy, and specialize in specific product areas.
the next thing is overweighing an idea of "artists don't want to piss off their poor fans over the long run". huge assumption. it doesn't matter how an artist stops filling venues eventually. if it happens it happens. "ack! its because I priced my Red Rocks performance too high on April 30th 2016" mmmm, no.
The artist/fan relationship is everything.
For a scalper to jump in and say "I can extract more profit by buying all your tickets and fleecing your fans" is parasitic, it is rent-seeking provides literally no value to anyone besides the scalper. And the scalper doesn't care about the artists or the fans, just rent-seeking profit.
There are laws against scalping in many countries for good reasons.