Basically, yes. If it's smart it almost always has to connect to another piece of hardware and since your wifi is already there. Why not piggyback on it?

There used to be some "smart" devices that you could program to work off a clock that was built into the device or hardwire to a separate sensor or something like that but I think they're all gone now. Wireless is just too convenient and the data that can be taken from you is just too valuable to pass up.