Let them eat competition.
Unless you mean specifically textbooks, which are inflating because piracy has destroyed the demand (the annual revenue of the textbook market is down ~33% since 2014, despite increases in both prices and enrollment in colleges). You can see the causal link here as increases in pricing are lagging decreasing sales. If the prices were driving the decreasing sales you would expect the opposite behavior.
https://archive.attn.com/stories/1164/heres-exactly-why-coll...
Between 1975 and 2014 college books outpaced inflation over three times.
BMW is a trademark. You can't take a Kia and put a BMW badge on it. You can, in principle, make an exact replica of a particular BMW model and put your own badge on it, and in that sense BMW doesn't have a monopoly on "BMWs" except insofar as some of the parts may be patented or (for the software) copyrighted. But that isn't an analogy, it's the original thing.
Notice what happens when you take the original thing (intellectual property) out of the equation, your statement becomes "Bayer has a monopoly on aspirin", which they don't, because the Aspirin trademark became generic and it's not under patent.
Taking intellectual property out of a conversation about intellectual property has predictably strange and totally irrelevant results. Why is that surprising?
There’s a two-sided marketplace for creative works, where publishers need to get works from creators and license them to customers. They want to maximize their own profits, but they also need to make a certain amount revenue as all methods of distribution have fixed costs.