This vexes me. It vexes me very much. Because when I purchase a book, I expect it to be a professional product. I expect it to have been proofread and edited. I find lack of proofreading as unacceptable as, hell, substandard glue in the binding; a book with typo after typo is as unreadable to me as one with its pages falling out.
Just plain unprofessional.
And look, I want to support the publishing industry. If only because I'd like it to still be around when I get around to finishing and submitting *my* books. Right?
But publishers, please - why should I pay you if you're not doing your job?
And keep in mind that I want to pay you. For serious. But just like I'd be annoyed if I bought a necklace and had it come apart in my hands, I get annoyed when I buy a book and find that it's chock full of typos, continuity errors.... one book I read recently changed a character's name three times and had the clear editorial note [name of the ship] in one place instead of the name of the ship. I kid you not.
EDIT: And yes, I would probably be less tinyfistsofrage if I felt healthy, but I don't. So. This never fails to annoy me, mind.