genocide asked, "I never put the seat down. ... My question is this: Who doesn't look before sitting!?"
Besides us peoples? At least two of our cats.
Despite landing in it more than once (because they practice the "ready, fire, aim!" mode of jumping), these felines still get completely shocked when they end up wet.
One of them is getting better at midair turns, though - the last two times someone left the lid up, she managed to do a 90-degree "flip" and only got her tail and one back paw wet. Of course, she still walks around looking thoroughly indignant.
(You thought it was bad enough getting the cold shoulder from your wife/gf/so after you left the seat up - try sitting down to use it while being glared at by a wet cat...)
Lady Niniane