If you firmly believe a baker should be able to refuse to bake for same-sex weddings, how can you think a restaurant owner us wrong to eject the face of the Trump White House?
It’s not discrimination if you object to the specific actions of an individual – that’s an opinion. Were restaurants to wholesale refuse to provide service to anyone who works under the Executive Branch (hard to ascertain that subset of people, but pretend) that might be discrimination based on political affiliation. But if a baker’s free speech / religion rights permit refusing service to individuals who wish to marry someone of the same gender … how do free speech / religion rights not permit refusing service to Republicans as a whole?
The problem seems to be, again, people conflate the freedom from government enacted punishment with freedom from consequences. You have the right to assemble and spew whatever white supremacist rubbish you want. But you may find yourself fired. Or court marshaled. Or ostracized in your neighborhood.