If you have a passing interest in film and animation, you've likely heard of Coyote Vs. Acme, a feature film in the Roger Rabbit tradition of blending 2D animation with live action focusing on characters from Warner Brothers' Roadrunner cartoons. The film would have focused on Wile E. Coyote suing the ubiquitous Acme corporation after decades of selling him faulty products, and by all accounts appeared to be a passion project from everyone involved. The movie was, in fact, complete and ready for release- only for Warner Brothers to kill it at the last possible second in the name of a multi-million dollar tax writeoff.
Rather than take a lower price, you write off the 9.
Your taxable income is now $10. And your average profit per thing is $90. Which is good for stock prices.
Mix in Hollywood accounting, and you might even still not have a taxable income. Plus, those other 9 aren't competing against the 1 that made it. They're concentrating all the profits in one thing, which makes marketing easier
But really, it all comes down to manipulating stock price.