(Your also discounting drug users; but unfortunately those addicted and at risk are also the least likely to have the means to acquire the drug.)
Also sex workers, also trans women, also people from countries with a high prevalence of HIV in the general population.
For example there's a massive campaign targeting both men and women engaging in any sort of sexual activity that includes fluid exchange promoting usage of PrEP. One can see it in a subway and on local commercials on TV.
There's some new campaign now which unfortunately i don't quite recall but it is highly bizarre. It something along the lines of "equality. make hiv undetectable. Truvada for PrEP." or something like that.
If a drug user is doing something as stupid as sharing needles they're likely not in the right state of mind to take PrEP.
https://www.injectingadvice.com/v4/index.php/articles/harm-r...
I wouldn't take it unless I was a non monogamous gay man[0], the risks out-weights the benefits in any other demographics imho.
[0] not that I have anything against that per say, it's just statistically the most affected demographic