I dont really in favor of spending bitcoin over drugs,its just an insult of your hardwork.Why not spending it into something useful,we all know how drugs works,maybe it gave a good benifits to anyone but i dont think that is a better idea.
I am just curious it somebody really bought drugs or other illegal stuff for Bitcoin, will he ever share this information with us? I am sure BTC can be used for doing it, but dollar here is much more popular.