Probably because it's new - if you see the blade cp parts at Helihobby.com they are numerous and much cheaper.

Also, commenting on the blades, I sent an e-mail to John at www.jcshobbies.com and he believes the plastic blades he makes are about the same size as what is needed for the axe. I plan on buying a pair soon to give them a try. Cost about the same tower is charging for the wooden blades - down side though - NOT assymetrical and also since they are plastic I think your copter will be more prone to break somewhere else. I am waiting on new blade grips and my wooden blades broken them.

The CNC (Computer Numerical Control - CNC is just a term referring to how the parts are cut with a computerized mill - it doesn't mean aluminum, it could be any material, but in this case the AXE uses Al parts) blade grips made from aluminum look great - ugly color, but I'm sure a must once someone else makes them cheaper or tower drops their price.