The dog was not a coke fiend. He just like the smell of it.
:^)
Ironically, this actually can be a problem with drug dogs. Many years ago an Air Force dog handler told me that dogs getting accidental snorts of cocaine was very real concern, since the dose could destroy the dog's sense of smell and leave it fit only for guard duty.
(The image of a German Shepard Dog on Bolivian marching powder doesn't exactly make me feel warm and fuzzy either, come to think of it.)