Well, I have not had the chance to see any of the merchandise, so I'm speaking out of ignorance and I'm never fortunate with women-specific items (especially bikes and saddles, I find them totally uncomfortable, most of them!)...
But I would think that "ride like a girl" is appealing, it inspires the idea of items that are girly and maybe nice, colorful, or with some nicer design... So I guess if I see "ride like a girl" on the box I will at least stop and look at what's inside.
Not sure it makes sense, but it would make me curious to look at it or try it.