HugDoggy
Esteemed Citizen of ZV
I think the changing of ones scent might be part of hunting behaviour in an attempt to smell more like prey than predator if carried on the wind while going out for some "fast food".And thirdly, we are not the only species that alters their smell with the help of outside chemicals. Take dogs for example who wallow in carcasses or feces of some wild animals. Not sure why they do it, but maybe they think that it makes themselves smell more attractive in one way or another.
Clearly domestic dogs have no need to do this sort of thing any more, if they have plenty to eat at home, but that doesn't change the way their brains are wired about such things.