Why are guys such pigs?

It's amazing how disgusting people are in public bathrooms, I don't even want to imagine what they are like at home. I bet many do it on purpose, thinking it's funny how messy they leave it. The worst is when you really got to use the stall, and the only toliet that is left is the one that is unflushed and it's all over the seat. I'm not talking about urine either.