First, he’s not a government official. But it’s easy enough to call another cab. Plus, I doubt that a muslim would refuse a ride from a passenger carrying booze. In most states, I think it is illegal to have open bottles in a vehicle.
I get that he’s not a public official but why should they be treated differently than a private citizen. There have been several cases of mzslim taxi drivers refusing passengers carrying booze. They created quite a stink here on FR.