Interesting. I didn't know that Avery Dennison's "intellectual property rights" extended to quashing other's right to free speech. Welcome to the New Corporate-Controlled America, folks.
(And the whole "deep linking" thing was found to be legal, oh, around 2001-2002 or so. Perhaps A-D's lawyers should review those decisions.)
They do have a right to prevent people from reproducing their offer in its entirety (copyright), in the case of a printed offer form, but they don't have any legal right whatsoever to limit someone else's free speech rights or the right to link to a publically-accessable internet web page. If they don't like it, they can piss off and move to Communist China for all I care.
Just the fact that they even think that they can assert those terms, makes me want to boycott them entirely.