Is this really a thing?

If they have Medicaid (wisconsin at least?) can they pay cash if there is one of these rejections: 1. prescriber not covered 2. commercial health ins must be billed first, but they state they do not have commercial ins 3. refill too soon: mainly for a vacation supply and they don't want to wait for us to call the insurance since it is Friday night and ins isn't open until Mon am? If we can't bill cash, where is proof I can hand to them so they'll believe me? Someone asked for proof I... Is this really a thing?
Source: Student Doctor Network - Category: Universities & Medical Training Authors: Source Type: forums