My mother saw a HUGE snake at CBR. It was on the 1st floor walkway (luckily we were on the 2nd floor). She said it was a moccasin (and we live in LA...see plenty of them...so she should know). She went into the room and called the front desk. They sent someone right away who caught it and put in a box and took it away. It could have very easily gotten into a 1st floor room if the door was open.
We are very used to this at home, so we know not to leave the door open. I can imagine people coming from other places may not be used to dealing with this and not even think about it.
Last year at POR, I was walking around the resort one evening and I saw some young kids playing on the cypress knees at the edge of the river. To me, that is just downright dangerous. First of all, if you fell on one it could cause serious injury. Secondly, I know that snakes love hiding in those sorts of spots. Just not a sensible thing to do. When I said something to them, the parents pretty much told me to mind my own business...which maybe I should have been doing anyway.
Not just in their rooms, but people need to pay attention to where they are walking at WDW, too. Especially walkways near bushes and/or water.