What you can't do is refuse to sell someone something that you are willing to sell to others simply because you don't like some identifiable trait.
-Simon
But isn't that exactly what happened? A gay couple came in asking for a "wedding cake". The wedding cake was not gay. It didn't have a rainbow flag on it. It wasn't topped with two people of the same sex. It didn't have a fabulous unicorn throwing up a handful of glitter on it. Etc.
The business owner was asked to bake a cake for a couple that happened to be gay. They WEREN'T asked to bake a gay cake. This is an important distinction.
I really enjoyed you analogy you gave about a black business owner asked to bake a cake with the confederate flag on it. I can definitely understand why they'd want to refuse. And conversely, if a Christian fundamentalist were asked to bake a cake with a rainbow flag on it I understand why they'd want to refuse as well.
But that's not what happened here.
"The case, Masterpiece Cakeshop Ltd. v. Colorado Civil Rights Commission, goes back to 2012. In July of that year, Charlie Craig and David Mullins, a same-sex couple, went to Masterpiece Cakeshop in Lakewood, Colorado, to try to buy a cake for a wedding reception. The owner, Jack Phillips, refused the request, arguing that due to his Christian beliefs, he opposed same-sex marriages and did not want to do anything that looked like an endorsement of a same-sex wedding.
Craig and Mullins filed charges of discrimination in response, citing a Colorado law that prohibits discrimination based on sexual orientation by public accommodations (places that are open to the public, such as hotels, restaurants, and bakeries)."