people are so weird

so today, i was sitting on the bus coming home from class, there's maybe five other people on there with me, so pretty much empty. so, since it was empty, i put my foot up on the seat next to me. at the next stop, a girl gets on and sits on my foot! on an EMPTY BUS! so, i just pull my foot out from underneath her and she just sits there, doesn't even look at me or say anything, as if nothing just happened.

why?!