You sure about this? Companies ask us not to use their brand as a generic noun because common usage can cause them to lose their exclusive use of a trademark. I recall ads by the Xerox corporation asking people to use the term “photocopy” as the noun or verb, and only use “Xerox” when referring to Xerox brand products, specifically because they were worried about losing their trademark. From reading their ad, it sounded like what made the difference was common usage.
The alt.usage.english FAQ has a long list of common words that were once trademarks but lost their status for this reason. Ones I can recall are aspirin, oatmeal, gasoline, kerosene, trampoline, and zipper.