Once I've been using free wireless in the JFK airport. But my laptop ran out of the power. I found power socket in the floor near the phone booth, and plugged in my laptop. After some time security guy came and told me that I shouldn't do that.
So when I was passing to the plain, they looked through all stuff from my luggage. Then they apologized "for the mess"
I've never had issues plugging in at JFK (or ROC - the two airports I fly between). A security guard has politely asked me to move before, but that usually happens when I start hogging the outlet for > an hour (layovers, wait before flight if its a long flight, etc). And I can understand wanting to keep the outlets free incase someone else needs to use it; usable outlets are sparsely spread out at airports.
