I have a Medicare Advantage Plan and they provide a $150 benefit towards either eyeglasses or contacts, but I have to pay the rest. I'm sure between Medicare and Medicaid you qualify for
some benefits. It's a possibility that the place you went to just doesn't accept Medicare or Medicaid as insurance, but there are plenty of places that do.
It's worth looking into what eye wear benefits you get from Medicare and Medicaid. Your case worker should be able to answer that question, but you can also call Medicaid/Medicare or try to locate the info on the web.
Good luck BF