Gay guys are likely closer to females in terms of frequent frivolous spending, i.e. spending on clothing and other accessories. Not that guys necessarily spend less, but their spending is more focused and comes in bigger chunks at less frequent intervals. Also, gay guys, like women, are more fashion and image conscious which means they'll buy into fads more readily and willfully overpay for products they fund appealing.
Umm, Not all of us? Trying to draw a connection between gay males' shopping habits and straight women's habits is superficial, and keep in mind that "gay male" is not a single population.
As one of the aforementioned gay males (and a 5-digit UID Slashdot geek), I should point out that my boyfriend and I certainly don't spend on "frivolous" things. He's more image-conscious than I am, certainly, (blame Gilt Group's iPhone app for that), but neither of us is "buys into fads more readily" than any other guy. We both have more cash because we both have pretty good jobs (game developer, sw architect) and we invest, save, and (currently) have no kids. I, personally, buy what I want, when I want, but not "fashion accessories." I buy experiences (e.g. flying into the grand canyon), and nice things (e.g. my shiny new Weber Genesis Grill).
I agree that orientation is irrelevant, but you should take a step back and reconsider what you wrote.