A company refusing to produce a specific item for a person because they feel it is inappropriate is not discrimination unless they're providing the same thing to other people.
A person refusing to support a company because of the actions of its staff/owners/etc is not discrimination.
I'm not so sure. Maybe they were brought up that way. You can't choose your parents or your religion in that respect. Muslims have a choice to be Muslim or not, should it be OK to discriminate against them too?
That said, we still need to draw the line somewhere if we want our laws to be effective. And the universally intuitive place to draw it is between biology and environment. The result is that environmentally unlucky individuals will get screwed so the rest of society can flourish. So yeah, if you had racist parents who brainwashed you with neo-nazi doctrine, I'm fully okay with the government not requiring that you be accepted by society.
Religions are a touchy subject for many, but I don't personally believe they should enjoy any special protections. And I say that as an atheist who'd be highly discriminated against by many, many people.
I'm trying to establish an objective rule for what kinds of discrimination you believe should be legal. You described each situation but you didn't actually make a value judgement (which was the whole point of the question).