Insurance..who are they to decide.. we pay them to work for us??

What insurance agency would allow to pay for such surgeries for a "Sleeve" I just got off the phone with blue sheild of Alaska and they won't. I have no insurance and the company i work for when they decide to give it to me, is that lousy "Cobra" who wont even allow a flu shot.. Do i mention that i want this type of medical procedure when shopping for insurance?