You teach people how to treat you. Kids do this because they can.
Parents enable their children to stay there because it's easier.
These people are out making bad decisions and you're picking up the tab for it. You're not helping by allowing children to come home and be non-productive. If people don't require enough of themselves, you have to start requiring more of them. The biggest mistake in motivating children is not allowing them to be who they can be. We're seeing people who are fixed in the teenage years.