But the trend really gained traction with the success of Jennifer Lopez's perfume "Glow," which was launched in 2002 and generated more than $80 million in sales in its first year.

Since then, the trend has reached a fever pitch, with perfume counters surrounded by ads featuring famous faces including those of actresses Gwyneth Paltrow, Nicole Kidman and Catherine Zeta-Jones.

For celebrities, product branding gives them a new line of income. For marketers, it is often an easy way to sell a product because celebrities are already well known.

"The marketing effort does not have to be as strong, because the celebrity already comes with a fan base," said Kenneth Hirst, founder of design firm Hirst Pacific, which designed one of Jennifer Lopez's perfumes, "Still."

"Celebrities cross borders. They have fans everywhere."

When Madonna was the face for Versace, consumers' perception of the brand fell 7.3 percent, meaning they were less likely to buy a Versace product, according to research firm Brand Keys, which studies brands.

"What you got with Madonna is someone who as a performer is always reinventing herself," said Brand Keys' president Robert Passikoff.

"For a performer that is a good thing;, but as a standard bearer for a certain set of values, it's extraordinarily schizophrenic, and that is what happened with Versace."

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