Yeah, I'm not sure how we'd effectively have a team of artists working on a bunch of different shots simultaneously on the same project if the files had to be synced locally before they could use them.  We're constantly updating an asset, bringing in a new version of the 3D render to comp while it's still rendering, using Render Garden to distribute a render that's going right to an editor, etc. and all of that needs to happen immediately -- it doesn't work for something to sync overnight.  We sometimes even sync entire projects from our network drive to Dropbox so remote freelancers can work on them as well.