Not really a waste of time. If no-one likes his price, then he isnt going to buy any. You are wasting his time by replying in his thread, making him think there is a constructive reply.
If you dont like a thread, dont comment. Mods are here for a reason, this is not a self Policing zone. The more you comment in threads like these, the more it gets bumped right back to the top. Leave it and it will die.