With my ex-mag-hag pedant hat on, in most shops they're not "in" the men's lifestyle category, they're next to it (same for motoring, leisure etc). This is because more men buy them so they put them where they are more likely to see them.
Obviously there is something chicken-eggy in there around whether more women would buy them if they were in their faces but buyers are v risk averse and limited on space, so you would never get these mags sited in both male and female categories.
I've seen Private Eye all over the shop (excuse the pun), and it's a constant struggle for mags like The Week, Time Out, New Statesman etc to find a position that makes sense, especially in supermarkets with limited numbers of mags on display.
Napdamnyou what you say is v interesting, makes me wonder how much of the positioning for "unisex"-type mags is ad-driven rather than consumer-driven I.e. We sell ads for aftershave so we have to see the mag in/next to the men's section. There are so many more women's mags for advertisers to place their "women's" products, it's easier for ad sales to cobble together a "men's" portfolio to sell across that includes music etc, that then means it's sited with men's mags, readership is mostly men, so ad-sales focus on men, etc etc in a big circle.
Anyone still awake? Sorry for how long and dull that was, but I can't bear to delete it all 