I don’t know why anyone would want to even buy the book.
Even if you were curious about it, you could sign it out of the library. Nearly every library carries it.
Although I have never read it, by all accounts it is rather dull tract and not worth the time it would take to get through it. Although Hitler had a charismatic speaking style, his book is extremely dull and boring in comparison.
Neo-Nazis. White supremacists. There's a niche market for it.
Even if you were curious about it, you could sign it out of the library. Nearly every library carries it.
Heck it's available online so you don't even have to go to the library.