In my previous life (as a paralegal, that is) I handled a good deal of trademark issues for a major franchisor. So, I understand what you are saying very well. My best personal example is that my husband, an IT manager, used to work for Velcro. Velcro (the company) sold hook and loop fasteners (the product). Yet, most people assume that the product, itself, is Velcro. I happen to know that Velcro USA often sought a clarification of that distinction in the courtroom.
Yes, there are lots of good examples - kleenex, thermos, escalator, aspirin, etc..