Path does not spam users. Invites on Path are never sent without a user's consent - any allegations to the contrary are false.
Even if one takes every reefer madness allegation of the prohibitionists at face value, marijuana prohibition has done far more harm to far more people than marijuana ever could.
William F. Buckley, Jr.
To thine own self be true, and it must follow, as the night the day, thou canst not then be false to any man.