I Am The Best: thanks for answer. May be, may be not. This is question of demand elasticity and there are only three ways how to prove it - persuade fencer, set up your own site or pay marketing researche. And I think all of them are unpenetrable.

I did not match other prices on other sites, but I would say this site belongs to cheaper ones. Even in global economics depends on country of origin and price of work is here much lower than in US.