Can a nonreligious/secular or atheist person be homophobic? And what reasons would they have? And is there any secular arguments against gay marriage?

Yes. From a practical standpoint, homosexual relationships are detrimental because they end bloodlines and do not procreate. Furthermore, "marriage" has always throughout history been a specific type of relationship with the express purpose of starting a family/having kids, even in polygamist societies. The entire reason why non-theocratic governments would even be involved in marriage, mainly through tax breaks and benefit programs, is to encourage the creation and growth of families. Certain western governments are in fact doing the opposite however, and actively undermining and discouraging the family.
Ya it's a lot of people. It probably happens more to people raised religious but end up black sheep of the family. The guy that thinks gay guys are gross but jerks it to lesbian porn. I remember older women that refuse to touch other women pass a hug and kiss on the cheek for family. Because it's gross and icky.
That's basically the same arguments with religious beliefs "gross and icky"
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There is an argument that members of a speces have an obligation to procreate to ensure the survival of the species.
They will be the first one to be. But will also lie about not being one, if it means (s) he gets one up against someone religious or agnostic.
there's plenty look at the comedian Patrice 0 Neal
He want to have the freedom to mock and bully Gays
I would guess they could be, just like anybody else
what reasons could they have? biology, society, peer group, wanting to mock whats weird or different etc
I think the “eww” factor is more of a reason than any. Even is behind the Bible’s hatred too.
of course they can many are
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