Absolutely not true. Programs in "main" don't recommend any proprietary crap
(you are referring probably to contrib which is off by default as it is
non-free). Have you even used Debian?
>Iceweasel for instance uses Mozilla's extension site I believe.
So what?
He who wants to install a proprietary extension for the browser WILL install
it on Debian just as on Triskel or whatever. Iceweasel doesn't recommend
anything.
The few packages with the Artistic License 1.0 are all double or triple
licensed with GPL or some others approved licenses.
