Yeah, I hate it when people use the Amazon rating system to whinge about things unrelated to the quality of the book. Sometimes people complain about the physical quality of a
used book or the service of a second-hand book seller. That's as constructive as using Amazon.com to complain about the service you got at a bricks and mortar bookshop.
Apple was having a similar problem with people give low ratings to iPhone applications they considered overpriced (but probably hadn't even bought). They now only allow you to rate apps that you've bought and this seems to have fixed the problem. Pity Amazon can't do this. They have introduced "
Verified Purchase" tags which could be used to weed out illegitimate reviews but it will be hard to do so while preserving genuine reviews from readers who didn't buy the book through Amazon.