on-topic: If their intention really did happen to be 'staying neutral in the culture war,' then their objection, I guess, has merit, at least superficially. Problem is that unless they find an uber-rare example of the hetero person who is 100% asexual *and* essentially expresses no emotional desire for a member of the opposite sex, they can't stay neutral. By default, straight people are 'openly' straight. The objection makes superficial sense, in that DeGeneres is a very open icon of the LGBT community, and that staying neutral on a political issue is good business - but good luck finding a truly 'neutral' person. And if they can't, as is the case, then there's no reason why not to market DeGeneres: she's an incredibly popular and well-liked individual who probably carries extremely high marketability.
...but more importantly, it's obvious that this is not a genuine desire to 'stay neutral in the culture war.' I just feel compelled to act as though they really are genuine, and defeat their argument on those grounds, so that they have no logical appeal at all.