I hear you, but who says that $500 is a reasonable price for a mattress? I'm sorry, but looking at the raw materials involved (don't even get me started on the frickin foam ones that don't even have springs: I'm looking at you Tempurpedic) it's clearly still a racket at the Sam's Club prices.
If it is the raw materials, and not a rip off, then why do solid foam rubber mattresses cost more than mattresses containing moving parts and metal springs?