I've seen two comments now about how the price factor is something inherent to the whole point of the Nexus line.
This isn't true.
The whole point of the Nexus line was to be able to get a handset that ran an unmodified version of Android, with software updates that weren't encumbered by the carriers or manufacturers, that weren't SIM locked to a particular carrier, and that had incredibly easy access to unlocking the bootloader (and thereby giving access to rooting / different ROMs).
I've been using Android phones since the
ADP1, and have used every Nexus phone ever released, so I kinda have some experience with these.
Low price was never a tenet of the Nexus line, it was just something that came around when the Galaxy Nexus came out (Nexus One and Nexus S were full retail price at release). Also of note - when the Galaxy Nexus, Nexus 4, and Nexus 5 were released initially you could only get the 'subsidised' price for the non-SIM locked handset direct from Google. If you bought the handset "off-contract" from anywhere else, it was full retail price.