It would make sense that a restaurant in a Democrat state in a Democrat city would segregate people based on color.
It also makes sense that a white Democrat would kick out a black man, regardless of political party.
Most likely, the black family was the only family asked to show Vaccination cards, being how Democrats are the party of hate, the party that fought a civil war to keep slavery, the party that was and is the KKK, the party the opposed the Civil Rights acts of the 1960's. Democrats simply need a reason, like vaccinations, to kick black people out of their businesses. Even if the black people are Democrats!