i read in an article that there was a assistant surgeon in usa whose name was Harrison .T. Mu, who was a neurosurgeon. he charged 117000 dollars or approximatiely 87 lakh rupees for a surgery. why did he charge so much? is it legal

if i am a neurosurgeon and have my own hospital with all basic facilities and visit two other hospitals and do 80 to 90 surgeries in a month , how much will i earn