A bakery refused to serve Joe Biden. A caterer wore a Romney shirt while serving Obama's food. Now, look, I think the Riverside Grill has it right: They don't care about their guests politics. "Just bring your money."
Now, I'm more OK with what the bakery did. From their explanation, it is clear that Biden wasn't asking for someone just to serve cupcakes. The way they explain it, it seems they thought that the campaign wanted to use it as a campaigning stop. So, maybe that was just some miscommunication between the two? I don't know. Maybe since I don't own and operate a small business, I just don't get it, but I think I wouldn't care whose money I was taking to operate legitimately. Heck, shouldn't I feel a smug satisfaction being so damn good at what I do, people I don't like are giving me money?
But, it is just tacky to wear the opposing team's colors when you're being paid to be there to serve. Man up, shut up, and do your job. Believe it or not, it is possible to do a job without letting politics color the occasion. It isn't like you were being sandbagged into serving the KKK. He isn't just the President of the United States, he's your customer. Even if you don't agree with him, I feel like it is rude to go out of your way to embarrass him.