Web Designers And Developers Always Have To Pay The Price For Older Browsers, esp. older I.E versions. Lot's of people especially old folks and computer illiterates still use them due to the fact they know very little About Browsers and updates, Why Can't All the Older Unsupported version be Killed.
How?
Same way browsers or any other software get prompted(their users get prompted) there's a new version once they connect to the web, then told they should click 'update' to update, all users of older browsers would be prompted "thisbrowser is just stupidly outdated, it'll self-destruct in 10 secs, and the latest supported version would be downloaded automatically, sit back and enjoy" Problem solved!