I have also been annoyed by damaged books and is one reason I avoid Amazon. I've had them arrive damaged from specialist online book stores as well, but not as often. The only way to avoid that is to go to the book store and inspect the product first (which I do on occasion).

They don't seem to be damaged in transit, usually it looks like they have been dropped or badly stored.

I always price check Amazon too, quite often it is not the cheapest, and you can get caught out on shipping costs as you say.