When people went through or analyzed their Web logs, bandwidth was expensive, and a page load was often 1 small HTML request plus maybe a GIF/JPEG or 3... the addition of these favicon requests was annoying. Also, Microsoft was widely disliked by Internet people, so this didn't help.

Another funny thing about the favicons... Sun had a template that a lot of people ended up copying, but the file format contained multiple resolutions. So it wasn't that unusual to see a Sun favicon logo on a site that wasn't Sun, because some site developer or Webmaster used Sun's template, replaced only the one for the resolution they used, so it looked good to them.