Back in the mid-70s when cocaine was the it drug (because it never failed to get you laid), my former college friend who lived with me after college, until he was imprisoned for 2 years, was getting pharmaceutical cocaine in significant quantities.
There is no comparison to the crap they sell in DR that is processed with gasoline, not that I would buy it!
But that pharmaceutical was the real deal and I do have some fond memories but knew when to say no más. My roommate didn't.
There is a lot of debate on this , but I think they used DIESEL FUEL , not gasoline..
not that it matters with respect to your Story.
I honestly never heard of or ever ever saw Pharm grade Cocaine? Interesting. and I lived in NYC during that time exact Period, where every OFFICE/ Birthday party someones House had the stuff on the Coffee Table just like in the Movie Boogie Nights .
Thinking back on it is Frightening, and amazing we all survived , because many people literally had Heart attacks ..
One Athlete died on the Basketball Court as I recall.
the Stuff was never the same twice and you could easily " not feel your Face" and you knew it was too Pure .
The 80's were a Wild time .
Like you said though, some people did not know when to stop, and Literally went Bankrupt, Lost their Jobs, Family, or worse .