That's a good question.
Maybe the other makers are just charging too much.
By the way Ibmikey, I've heard that it is best to buy a new barrel that has already been fluted as part of the production process, rather than having it fluted by a gunsmith later.
I believe that it has something to do with altering the straightness & dimensional consistency if it's not done prior to reaming the inside diameter of the barrel blank or prior to final stress relieving and lapping.
Of course I doubt that it would make much of a difference when blasting golf balls at 50 yds. with a .308, but I thought I'd pass that along to you anyway.