I am not making your point if you beleive in reason and logic. 
I am not going to engage in your ridiculous and offensive fantasy situations. 
You keep talking about "freedom of expression." You obviously do not know what you are talking about.

I assume you are talking about the first amendment. 
This part: "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof;"

Making a cake is not religion. 
You do not have the right to discriminate.
You do not have the right to not be offended.


If you,want to lobby to make it legal to discriminate, do it, that is your right as a free American.
Regular Americans like me do not like discrimination, even if we are not ever the victim.