if static assets arent being requested from their server then it would not contribute to your bandwidth meter

You still have to transfer that data through the network pipe to the end user no? How the server itself accesses the files to do so seems irrelevant to me.

I think if the assets are served in the html from ipfs gateway, then it doesn't add to your outbound traffic. Also once browsers support natively ipfs:// static content the game changes and the IPFS party really gets started.