Sieglinde
There are two important things a secular society offers to people of all religions and none:
Principle 1: Freedom of belief. The state makes no judgement over what is a legitimate religious belief or a reasonable religious practice. That is up to an individual's conscience.
Principle 2: Non-discrimination. The state religion a protected characteristic - employers and others cannot discriminate against a person because of their religion.
I think these two things are valuable. Don't you?
I don't see how society can maintain these two principles and at the same time make exceptions for people of some religions.
For example, if you give an exemption to principle 2, that says that employers can discriminate if it is on the basis of their own religious belief, then you have pretty much given anyone a license to discriminate, since under principle 1 the state does not get to decide what is a legitimate belief.
Or if you say that only members of certain religious communities are able to discriminate, then the state has to take a view about which members of which religions are allowed to claim which beliefs - i.e. you've given up on principle 2.
Furthermore if you say that religious purity laws take precedence over these principles then an employer would be discriminating if they refused to hire someone whose religion made it impossible for them to serve certain customers, work with certain staff etc...
No one is forced to hire anyone. But if you do choose to become an employer then you have to within the rules of employment law.
The point about racism - is not that christians want to promote racism (although some clearly do promote homophobia), but that racists and homophobes could then claim that this is part of their religious belief and would be exempt from discrimination laws.