Then I overheard this conversation in a public restroom:
Mother: All done?
Mother: No, do not flush. That handle is dirty.
They then left the waste floating while they left. They did wash their hands.
I just wanted to scream at them! How many people will now avoid that stall because it might be out of order? Do you think public establishments have someone who just runs around flushing the toilets periodically? You need to wash your hands anyway after wiping your naughty bits, so touching the flush handle is not going to harm you. If you're that skittish, wrap some toilet paper around your hand and then throw it in the trash before you wash your hands.
This behavior is why we need toilet police, not stalking!