Absolutely but once you have a non-shark source for the substance, you might as well be able to replace other uses.

Looking from a different angle, I can see few valid reasons for using cosmetics:

1. Cosmetics often includes medical/dermatological products which are essential for some people.

2. Cosmetics can be used not just for "vanity" but to cover big scars and other unwanted-attention-invoking skin conditions; similar to how plastic surgery may be life-saving for some folks and enable them to live a "normal life".

3. Seeking beauty/aesthetics is not a bad thing in itself

I assume, though, most cosmetics are used for nugatory reasons, and we should always questions whether these above use cases really justify killing millions of animals.