Elsewhere on the internet
Men Taking Up Too Much Space on the Train is a blog dedicated to showcasing how easy it is for the masses to obtain pictures of men spreading themselves across two seats on a train, when they could easily take up one. It's framed, as much as any single serving Tumblog can frame an issue, as a demonstration of one of the myriad small ways in which the societal urgings -- that encourage women to be slight and small and above all not impose on others and that encourage men to assert their presence and claim their space -- manifest even in the smallest of ways.
Saving Room For Cats posits that it's not the result of subtle societal messages at all: it's because all those guys are saving room for enormous photoshopped cats. And sometimes those cats are saving room for other cats.