I've never understood why View Source would do anything but show me the source of the page I'm looking at - not the source of the page as it is "now," which could be seconds, minutes or hours later. If I'm looking at a page, the browser has or could have a copy of the original stream sent from the server, why not just display that?
What browser(s) are you using that have such behaviour? Is this a new "feature" in the very latest versions? I don't think I've ever seen View Source make another request on Chrome, Firefox, IE, or Opera.