It is extremely difficult to determine how much things will cost in the US system ahead of time and there is no reasonable way you can "shop" around for better prices when it comes to healthcare.
It's like you go out for dinner, but the restaurant won't tell you how much things cost, just that you should definitely order X,Y, and Z. And all the restaurants in town have the same policy. You order it, and then they mail you the bill 2 weeks later. Only for you to find out the exorbitant costs. Plus, they decided to charge you for the extra ketchup you requested.