I've never understood the reason for them. You're never going to be able to demonstrate how something smells over TV or the Radio or posters. I guess people need to know the product is out there but jesus... The Brad Pitt one is making me particularly irate at the moment. He didn't need to do that. It's for women's perfume anyway. He hams it up so badly. I rate him as an actor normally but he's made himself look a grade A wanker.