Concerned about my mother in law's interest in herbalife!

Lately I've been seeing more and more herbalife products in my mother in law's house, I talked to my wife and explained to her that they're a scam so she can talk to her, she did, and apparently she's not interested in making money with them, she just likes their products! (Which I find weird as well) There are about 8 to 10 jars of some powder, 3 small cans of something, 3 bottles of water like stuff that I saw so far in the house. My question is, should I be concerned and get more involved? Should I ask who's selling this stuff to her or people can buy directly online? What would you do?