[bellyfullofbac]

I mean, the precedent has been there for a looong time, and grandparent commenter certainly didn't set it...

As to the why, it's probably related to social status. In the old days people paid attention and listened to the people with status (who usually became leaders), nowadays with celebrity culture it's somehow inverted, a good looking person who can act or sing gets put on stage, and they get the attention (for singing, acting, or looking good), and they gain status.

[asddubs]

sure, but you can't really complain if people believe jenny mccarthy that vaccines cause autism if your counterargument is that keanu reeves said they don't. obviously we're not talking about vaccines right now, but I hope you can see my point