There is a group of smokers here and I'm going to attempt to get them to use an ash tray.
They weren't just dumping their ashes on the floor were they?
They were and were actually laughing about it.
I completely get where you're coming from with that request. They might not realize it but that's still considered littering which is both illegal and wrong. Hopefully they listen to you.
I know it is wrong and illegal, but they should do it anyways.
It's definitely wrong and someone is going to have to clean up the mess they leave behind. People should be tidy, especially in public spaces. I hope they listen to you and correct their behavior.