It's an individual choice. I like it a lot, and it's no different from discussing merchandise in a real store. Lots of people like sharing information, so some choosing not to is not a problem. PS: My experience is that the shared knowledge is excellent.
Mine too. We no longer make any large purchases without first consulting the amazon reviews. I'm sure some of them are put there by manufacturers themselves, but no question if a product has a propensity toward a specific defect, you'll read about it in the customer reviews.