Illegal? Why? Illegal is something that is done out of established laws, and free market I don't think is illegal. A different thing is that we may advise newbies that some item is overprices, but even in that case, it will overpriced form your personal view. You may not give importance to have a watch with a serviced movement because you know how to do do it or have access to some one that can do it, or you don't, so service is a plus you would pay.
Please, don't try to be so protectionist... market regulates itself easily without any need of external help.