Sharing is caring but not for everyone

I am interested in a product but I want to share with my friend with the product. So I asked if she is interested to share with me to purchase them. But she is not interested, I can understand why she is not interested.

It is medicine that I am interested and she is interested to eat at all. It is health supplementary vitamin which I want to buy. Anyway I am going to try my luck next time.

Have you ever share buying things with your friends? If yes what are the products?