Hidden network warning With reference to the following thread (but without the security issue):

IOS 10 warning: Using a hidden network can expose personally identifiable information

Unsafe or not... Could this be a potential battery thief?

*Edit: This thread was put on hold (because of too little info.), so I add a complimentary question here to mike's answer below...

Are you saying that the "iDevices" are making broadcasts the very same way for not hidden networks as for a hidden ones? In that case, what content is broadcasted for those networks that are not hidden? 

*Edit2: Please see discussion below. It would be nice if you could keep this thread open until it is answered.
No. The power consumption of WiFi doesn't vary if the SSID is broadcast and shown as hidden or broadcast and shown as not hidden.