Are you familiar with Broadband-over-Power-Lines (BPL)?
Michigan has it.
Are you familiar with RFID or NAIS?
How about the fact that some Chinese microchips are hardware Trojans?
CALEA?
Technologically it is possible. Whether it’s in use—and who uses it and why—is another matter.
I anticipate that it will be in use, if not immediately, later. Industry will want it for the advertising/channel-surfing information, if nothing else.
These devices have no output to such systems - take one apart yourself and see.