Absolutely, Michael.
Kate Moss (who I'm sure is no saint) entered the fashion industry at a young and impressionable age. It's an industry in which cocaine taking is rife. Catwalk models use it to stay awake, keep working and stay thin. The designers, photographers and others in the industry, including the media, also use the drug. Apparently the phrase "Do I smell Chanel?" is widely understood to be code for "where can I get some coke?"
Most fashion designers don't design any more. They rely on a design team and just get presented with the work for final approval. It's the designer's name that counts these days, not his skill. Apparently, one British designer who works in Paris is said to be such a devoted party animal that his backers, in order to protect their £3m investment, follow him round each night to make sure he gets home in one piece.
So, Kate Moss couldn't handle the long term use (I believe she's now in for a 'clean-out'). Few can.
Regards
Steve M