Because sometimes there are scrollable areas on the page that you want to pan, not scroll, but there's no panning built into HTML. Yes, mouse drivers should mak

Because sometimes there are scrollable areas on the page that you want to pan, not scroll, but there's no panning built into HTML. Yes, mouse drivers should make it possible to pan any scrollable area, but most don't, and websites have to be usable with shitty drivers.