I find it extremely dubious that you could actually infringe on a patent merely by using a consumer product. Disregarding this particular patent, is that sort of claim actually grounded in fact?
Well, if the product's manufacturer has licensed the patent, then the "exhaustion doctrine" generally keeps the patent holder from taking a second whack from people who bought it. That's what ordinarily shields end-users of consumer products from this kind of nonsense.
If the manufacturer hasn't licensed the product, though, the users may well be fair game, in the eyes of the law.
But end users generally don't know and have no way of knowing what technology is inside a product. That seems pretty sketchy. While it's true that unintentionally infringing on a patent is not an excuse, if I'm liable for someone else's infringing without my knowledge my potential liability is completely unlimited.
Whether it's grounded in fact has never been relevant because the in-court legal costs will far outweigh settlement -- that is the business model of patent trolling.
