Ghosts in the bathroom

So I've come to the conclusion that the 3rd floor women's bathroom at work is haunted. I say this because I'll walk in and the whole place will be empty, and yet there's still people-ish noises in there. Like the toilet paper holder will creak like someone hit it. Or there will be a shuffling noise, like feet walking across the floor. But all the stall doors are standing empty and open, so what gives? I've already explained the faint toilet flushing noises (from the bathroom upstairs) and the creaks in the walls (pressure changes in the pipes), but the toilet paper roll holder rattling? I'm still working on that one. Our building has been around forever, so it wouldn't be all surprising if there was lingering...we'll call it "energy" in there. A quick Google search tells me that this is not unusual, as "haunted bathroom" brought back 1,460,000 hits. It also tells me that most haunted bathrooms occur in schools. (I didn't want to hang out any longer than necessary in my school bathroom...maybe when you're dead, you find "Shelly loves Billy 4-ever!" more interesting). I guess when you gotta go, you gotta go...even when you're gone.