this is typical...Immature kids punish Foster parents for the sins of the real Parents. They try to believe that they can run away and erase the past. but life is tough for everyone in some way.
They "Blew it" when they ran off.
Now they wallow in self pity..and form their little "Victim" identity. justifing Lieing,stealing,and not really trying to work.
It all boils down to Rebellion, and blame of others.
they never get better untill they "Grow-up"
They probably don't even know what "growing up" is. Broken families are a pretty consistent theme. It's not reasonable to expect a person to understand something they've never been exposed to.