Anybody who knows a little bit wont get an expensive frame with 105. Thats just nuts. As TJ mentioned, they know who are they selling the bikes at, besides... Probably the margin for them is pretty high also... U can lie to somebody with money who has no idea that way because somebody who knows will go for the frame and get the stuff somewhere else or simply more the parts over.

A pinarello, a colnago or even a ridley high end models built with 105 is just heresy!!! Even with ultegra IT's a SIN!