Surgery centers do not have the cost of carry of a pharmacy(24/7), a fully functioning diagnostic lab(24/7), an emergency room(24/7), 200-1000 beds, ICU,CCU, radiology department(24/7) etc and an infrastructure that is impressively expensive.
Its very very very easy to offer these surgeries at a cheaper price than a hospital but when you need a complicated surgery or an emergency that surgery center will not be there for you.
I like the idea of pricing transparency but it should be hand in hand with outcome and quality statistics and comparisons should be fair.
I did not see Oklahoma surgery center compare themselves to other surgery centers which are likely very close in price.
One last thing. In healthcare - price is not everything (its an important issue) but as we drive down the price, we must not sacrifice but rather improve outcome measurement and quality.