If you are interested in - better yet, knowledgeable about - medical billing, perhaps you might read this article and explain to me why this practice makes sense.
http://www.nytimes.com/2014/09/21/us/drive-by-doctoring-surprise-medical-bills.html
By this practice, I mean doctors who you don't know and who aren't in-network to your insurance, coming in to consult on your case, without your consent or in this case your knowledge, and billing you for a large fee.
Basically this guy had a spinal fusion, his surgeon brought in a second surgeon to assist, the second surgeon billed $117,000 and the patient had to pay it, or rather his insurer paid it. The patient had never heard of the second surgeon, was unconscious when the doctor arrived, never signed any paperwork directly with that doctor.