Answer:
It depends on the backstory of the person.
Step-by-step explanation:
They could start buying it cause they want to seem cool, they are going through a hard time and think that that will help them feel better, because they were dared to, or because they were forced to. their are many reasons why they mite buy it, but it all depends on what is happening with them or what happened to them. all you can do is ask them if they are ok and if they want to stop and they don't know how either tell a doctor to help or set up a plan that they will be comfortable with. I hope i was useful!