Why don't scent supermarkets stink?

Something bizarre happened in a scent supermarket the other day. I was in there checking something out when two guys came in and one of them started spraying himself liberally with Bleu de Chanel.

Ok, nothing strange about that, but then he grabbed Sauvage and gave himself a dozen more sprays with that. Having seen the horror unfolding, I moved away to a safe distance. But, as the two of them left, I crossed his sillage and - nothing! I couldn't smell anything at all.

A friend said 'Oh that's the air conditioning, it must have sucked it away in a flash.'

And that's why scent supermarkets don't stink, apparently...