It's wrong to use your friends.
Tammy is hanging out with her friends at a restaurant but is broke.
Tammy wants to get some food.
Tammy asks a friend if he can buy her a simple sandwich and pays him back the next day after getting her paycheck.
Tammy asks her friends to buy her some food but never pays them back.
Her friends respect Tammy and trust her and help her in the future.
Her friends refuse to ever buy her anything in the future and resent her.