The fact that people bought ~60 of the things shows there is a market for it. Just extract the sensor from a FLIR ONE if it really bothers you that people pay more for convenience. Nate's got it figured out.
Forget extracting the sensor if you just want one. $250 for the flirone, $50 for a breakout board, smells like time for arbitrage, and then sell the battery or other scrap from tearing it apart as replacement parts on ebay too.
And hope that sparkfun doesnt see that the demand is decent, buy a bunch direct from FLIR at a good discount and pull the rug out from under you :p