I think it works the other way around too, especially with women just getting into it. I hear "I need a women's road bike" from someone who looks like she'd have better luck with the unisex frames quite a bit. I'll show them the women's stuff, of course, and then try to persuade them that they look cramped and perhaps suggest that they try a unisex frame. It doesn't always work.
I don't know if it's the paint scheme ("But I want the fun colors!") or an ingrained preference for the "appropriately-gendered" item (and marketing playing on that), or what.