Suppose, rather than fund an anti-gay-marriage bill, Eich had instead funded a fringe bill that prohibited black people from getting married. Or suppose he said during a press conference that he believed women shouldn’t have the right to vote.
Would it be reasonable for the public to be outraged and call for his firing then?
Assuming your answer is yes (I don’t think I can really help you if it’s not), why is that different from funding an anti-gay-marriage bill?
Spot on. Freedom of speech is not a license to discriminate.