I'm a biracial woman who has experimented with various drugs in the past (mdma, cocaine, ketamine). I've always had a diverse group of friends (black, white, asian).
I never really noticed that my other non-white friend did drugs/drank less until a close friend pointed out that her parents thought I was a bit wild for drinking a lot during a gathering at my parents house. It made me realize that I was definitely an outlier when it came to consuming substances.
None of my friends are religious or had particularly strict parents as they did drink/go out to clubs, but their drinking habits seemed to be very different to other Irish and English friends that would usually offer me something to drink when I hang out at their place. It also was totally normal for the teens/young adults to drink which seemed to be frowned upon when I hang out with my extended African family or the families of my other friend. I also know far fewer of them who have tried drugs harder than weed
I thought it was silly until my friend showed me a VICE article written about it:
https://www.vice.com/en/article/black-british-party-drug-use-tv/