Companies != individuals.

Companies do not (and should not, IMO) fall under the protection of discrimination.

It's different because it's about critical services with no alternatives.

Bake a generic cake for homosexuals, or bake a homosexual cake?

Legally its different because sexuality is protected so you may not discriminate based on it. How that list is chosen is somewhat arbitrary however.

A company cannot really have a religious believe.

This is just plain wrong. Look at all the religion-run hospitals in America, and how they use religious values to affect their patient care and which services they do and don't allow. This has been affirmed by the court system even.

I personally don't like it one bit; people should be getting medical services based on the latest medical science, not based on some millennia-old book of fables, but unfortunately that's the law and the situation currently. And you can't just say "go to a different hospital", because in a lot of rural or small-city areas, these religious hospitals are the only providers around, so they have a local monopoly.

As another counterpoint, just look at Chik-Fil-A. That's absolutely a religious company, and they're quite proud of it. I don't like it either, so I don't eat there (then again, I avoid fast food anyway), but countless Americans are either OK with it, or really like it.

You are talking about the religious beliefs of people running the company.

No, I'm not. These companies push the company's religious beliefs and values onto the employees, and onto their customers when they can.

A company is a government granted charter. Government has an interest in what the company does.