Where do you connect "Your business offers cakes, we would like to buy one please." with "You must make us a cake depicting racist slogans and nudity."

These two things aren't even in the same ballpark let alone the same sport.

Here's how an analogy works:

If the baker were to put a sign up in his business he'd have to have a menu of services with a section that said "Straight Couples Only". Does that not read as discriminatory to you? If he is allowed to do that then I should be able to open a grocery store in your neighborhood and label the bread aisle "For atheists only." That is the kind of country you think we should live in from what I can tell.