They are exactly the same issue. They only appear different to you because you want them to. The baker, florist and photographer are providing a for profit, commercial service available to the public. They are not being asked to 'partake' in religious services, only provide the services they are getting paid for to an event, which they certainly would do if it were a religious event.
They do not have the legal right to provide the service inside their building and then refuse to provide it outside based on discriminatory reasons. But I suppose you know more than the framers of the Constitution and all of the individuals who have interpreted it over the decades. We should be in awe.
Using your (again) completely wrong analogy a baker could sell a cake to a black person inside their bakery but would be legally protected to not take the cake to a black wedding reception. The courts have determined that your viewpoint is wrong, and they have consistently done so for decades.
It would be so much better for you and the other R Wing X-tian fundies to simply lose the hate, realize what type of country we live in (constitutional democracy based on utilitarian principles) and that your religious beliefs and practices end at this demarcation point. And that demarcation point is a very good thing.