I mean, you’ll find people using PEDs in any sport, despite the risk of bans and everything. Steroid use is also rampant among bodybuilders.
There is an “obvious market”, but why do such sport leagues or federations that openly allow those drugs exist?
I can imagine that such a thing existing would create an immediate and widespread health problem with lots of people, athletes or not, using those performance enhancers and accidentally fucking themselves. But what else could be a problem?
It’s already that way in cycling, for example. I guess the prohibition just allows the various governing bodies to avoid legal liability for any damage to the athletes.