Well even if eHarmony did allow gays to use their service, I doubt they would get much use of it.

eHarmony offers heterosexual matches. A homosexual obviously wouldn't benefit from being matched with someone of the opposite sex. I'm sure they could feel free to be, but I don't think they would be very satisfied.

Homosexuals want eHarmony to alter their services to cater to homosexuals as well. While that's fine as a request, it's a stupid demand, and I would guess there's nothing legal that's binding eHarmoney to cater their services to them as well.