Well, she could have done worse with grandma's debit card than buy BF $10 worth of gas so maybe she still remembers some of what you taught her.
I would give her doctor a private heads up about the smoking. It needs to come from them, not you. I know the doc can't reveal private into to you but I bet you could just leave a message with the nurse that 'Jane Smith" needs to hear about the dangers of smoking.
Many areas have resources and groups for pregnant teens. I would see if you can find one by you. I know some social workers who do the groups here and they have a great relationship with the girls so they are able to sneak in the good advice.
I doubt she will see the light until after the baby is born-it's just not real enough!
Love the idea of sneaking in a call to the Doctor about smoking. However she does not sound motivated at all to stop any of this. She's not going to change any time soon until her life becomes very uncomfortable and the adults stop giving her financial help.
I would encourage your daughter to highly consider giving this baby up for adoption. She may balk at the idea, but you might persuade her to at least entertain the idea on the off chance that she won't do well having herself tied down, no job, no income, delingquent Dad etc...
She might even be encouraged financially. Some private agencies pay big bucks for a healthy baby that they will in turn give to a good family who is desperate for a child.
If that doesn't work, please consider setting real boundries with her. I have a close relative who had this situation and is now raising the child. It was sad because he spent the first formative years bouncing from one unhealthy home to another before the courts appointed them as guardians. The young boy now suffers all kinds of problems as a result of his being raised by a young mother who never really wanted him in the first place.