You're joking, right? How do all of the sites that require Flash also not fall under this same statement?
(Yes, I'm being somewhat snarky, but I'm also genuinely interested in your take on Flash-based sites. Is it an issue of "Flash is already installed and QuickTime is not" or something beyond that?)
Yes, Flash is already installed. It also opens instantly and is never slow. It doesn't open up weird framed windows that don't match the chrome of the rest of the OS. It doesn't try to trick me into installing iTunes to download it, and it doesn't try to trick me into installing iTunes and Safari every couple of days when its separately installed software updater pops itself up. Quicktime (and iTunes) are just terrible software on Windows -- they perform poorly, make no attempt to act like Windows applications, and are almost on the level of malware when it comes to the updater.
(Yes, I'm being somewhat snarky, but I'm also genuinely interested in your take on Flash-based sites. Is it an issue of "Flash is already installed and QuickTime is not" or something beyond that?)