And alcohol, and sex, and......
Fact of the matter is all the things in life that are "tempting" bring eventual darkness.
Writing of law is what is in question, parameters become subjective.
Neither alcohol nor sex require one to interface with drug dealers who will certainly try to "upsell" the customer to other narcotics!
And, I think it's just puritanical to suggest that sex is a vice. Around these parts we prefer to refer to it as "baby making". :)