Specifically because of this:
http://en.wikipedia.beta.wmflabs.org/wiki/Template:Wikipedia%27s_sister_projects
The icons come from upload.wikimedia.org
Same issue other places as well, eg:
http://en.wikipedia.beta.wmflabs.org/wiki/Hurricane_Celeste_%281972%29
which loads the acrobat.gif from upload.wikimedia.org
Version: unspecified
Severity: enhancement
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=37245