You actually often can (or at least, could -- not sure how Obamacare might have changed this) -- you need to state that you are uninsured; you may very well get

You actually often can (or at least, could -- not sure how Obamacare might have changed this) -- you need to state that you are uninsured; you may very well get a lower price for your routine than you would have to pay out of pocket with insurance.