well, i'd say it to someone, especially a stranger. a friend i would know, and need not make any assumtpion. sounds to me like this guy was just trying to relate to you, make a connection, perhaps make your day or his just a little brighter.
what i really think is funny (and please don't take this as an attack) is that he used his experience (knowledge of marijuana cough) to reach out to you, and the tendency is to use your experience (knowledge of cf) to judge him for doing so.