Why are 7.1 pre amps more $$ than 7.1 receivers?

For example, I could buy a Denon 3311 surround sound receiver with massive connectivity (PC networking, Pandora, etc) for about $1100 (once it actually hits the market this summer) Assuming I already own a nice McIntosh multichannel power amp - I can't seem to find any pre amp 7.1 surround processors anywhere near that price range. Even used, the processor wont have HDMI and ethernet, etc. Any ideas? Why would one buy a 3 or 4 K pre amp processor when a $1100 receiver has more connectivity, etc.