Re: It beggards belief
I was annoyed by constantly switching on/off my WiFi, I found an app on the Play Store a year or so ago which does it for you (Wi-Fi Matic). It seems to be a good idea: Using the cell towers signal to remember where the user wants WiFi enabled, then when you wander away from that cell tower configuration, it switches it off for you. Of course, the user can override, and manually delete rules too.
Should be incorporated into a standard of some sort applied to all networking (bluetooth, NFC etc). I've noticed a couple of manufacturers starting to copy this functionality, so I hope the developer is getting some royalties/consultancy fees from them!
As for WiFi, IANAE but disconnected clients really should stay quiet unless they recognise the broadcast/ID of the network trying to talk to them, or the user wants to add a new network to that list.