>> Obviously they collect this information to be able to guide missiles and drones when GPS signal is jammed

> Are there a lot of missiles that travel slowly enough to be able to guide themselves via watching for nearby wifi signals?

Cheap, slow-moving drones are the hot new missiles on the battlefield of today. This often talked-about model files at 115 mph (https://en.wikipedia.org/wiki/HESA_Shahed_136).

In some areas GPS is spoofed and the displayed location is wrong. If, for example, a "smart" car gets a task from its manufacturer to film some secret object, it would fail if it relied only on GPS and did not use cell towers and WiFi points for determining its location. So knowing their location determines whether the mission would fail or succeed. So foreign devices should not be allowed to collect such information.

I think that might have been semi-sarcastic. I mean, there are lots of reasons to do this sort of thing, some are bad, some are not so bad, most are not war.