The problem is when I was a kid people in my little town would not sell minorities houses. I remember when I was about 9 (not really, hell I don't know how old I am right now, but I was really short) adults talking about blacks ruining property values. So, if a baker can not sell gay people a cake then realtors can refuse to sell black people houses, or gas stations would not pump black people gas when they drive through, or breakfast at the local diner. Do you see what you guys are saying? If you have the majority you can literally control people in your area.
This is the best argument so far, for the 'force them to do something they don't want' position.
I think the best counter-argument is this: as a default, we don't want the government to force people to do anything. The government's main role is to
prevent people from forcing others to do things -- to allow us to get on with our lives. It should just provide a framework for free people to live their lives as they want. This is the pure libertarian position.
But like all 'pure' positions, it runs into problems in the real world. For example, a pure libertarian position would allow parents to raise their children to be illiterate and innumerate. So we force them to educate their children. And we even force the childless to help pay for this, on the grounds that an educated population is a 'public good'.
But we draw the line there. We don't force parents to make their children fit, by having them run five miles a day. We don't force them to forbid excessive television watching. In the worst cases of child neglect, we do intervene, but these have to be pretty extreme. Basically, if you feed your children, keep them reasonably clean and well-clothed .. you are left alone.
On employment, we have, for the last fifty years or so, taken an interventionist stand, extending one that was taken even earlier, when we forced employers to meet certain minimum standards of workplace safety, working hours, even wage levels.
The libertarian model assumes more or less equally powerful individuals bargaining in a free market. The reality of capitalism is that the employer has far more power than the worker -- thus, various state interventions to right the balance a bit.
With respect to the race question, there was another evil that could only be dealt with by extending state power: there was fairly systematic discrimination against hiring Blacks, especially in the American South.
This had a real, and negative, impact. In the South, even employers that might have hired Blacks -- as some employers in the North did, to undercut wages -- were afraid to do so.
[This was a big issue in the 1930s when the UAW was trying to organize the Ford plants because Henry Ford had always hired Black workers, and the white workers were racist ...how the union stopped Blacks from being strikebreakers and confronted the racism of its own members is an interesting story, too long to tell here, but a good summary (a review of two books on it) is here:
Black Workers, Fordism and the UAW | Solidarity ]
So in the South, Blacks weren't hired even for many unskilled jobs for which they would have been hired in the North. This was not necessarily because the owners of the businesses in question were prejudiced. (I was part of a group, led by an eccentric Black, called the 'Progressive Youth Association' in Houston in the early sixties: among other things, we picketed the biggest downtown department store, Foley's, which didn't hire Blacks: DON'T SHOP WHERE YOU CAN'T WORK was our slogan. But fear of the prejudice of whites was strong among the owners, who weren't personally particularly prejudiced -- they feared losing white customers.)
So ... it required the law, one that interfered with the right of an employer to hire whom he chose. Then, the owners of businesses in the South could say to their white customers, "We're forced to do this."
In other words, a great evil -- locking Blacks out of good jobs -- required another evil -- expanding government power -- to counter it.
If gays were being denied some essential service, just because they were gay -- if, say, the only supermarket in town refused to sell food to gay customers -- we would have a case for extending the power of the government to force them to do so.
But this is a trivial, concocted situation. The baker in question has a strong religious prohibition against recognizing same-sex marriages. He'll sell them a cake, but he won't violate his conscience by making one honoring same-sex marriage. The gay customers can easily go elsewhere. No one has suggested that they can't get a cake from another baker.
This is purely a small-minded persecution of a religious person that has a belief that his persecutors do not like. It is in no way comparable to preventing Black people from getting jobs.
The value of this case is that it shows the totalitarian mindset of a section of the Left.
And there is hypocrisy here too. If fundamentalist Christians can be forced to bake a cake celebrating a gay marriage, why can't they be forced to bake one for, say, Satanists -- why can't Muslim bakers be forced to bake a cake celebrating Israeli Independence Day? Why can't a Black baker be forced to bake a cake celebrating the local Ku Klux Klan?
The totalitarian mindset cannot stand genuine diversity. It does not want to live in a world where people can disagree on things, but still get along together. This mindset is the greatest enemy of the sort of commonsense, give-and-take, mind-your-own-business that allows a community of diverse beliefs and cultures to co-exist.