Here's the deal, folks. I own a business that is open to the public. As such, it is my responsibility to offer equal access to all people. That is the American way, and I am a patriotic citizen who believes in the American way. If I sell a product to one person, I sell it to another, and I do so regardless of their ethnicity, gender, or sexual orientation.
The only wiggle room I can come up with in terms of bakeries, is that while they should be expected to provide a product to one person as they do the next, they should not be required to provide imagery or language they do not normally provide. If they bake a cake that says "best wishes so and so" for one couple, they should do so for another. If they do not normally depict Bert and Ernie holding hands or smooching, however, there should be no demands that they do.
It seems an easy enough concept to understand, but people on both sides of the issue get so caught up in their agenda that they fail to notice. On one hand, the homophobes will be deterred by nothing whatsoever, while some of the more radical gay supporters are so caught up in their own hatred of Christianity that they seek punishment rather than balance. .