So I am staying the night at the O'Hare airport in Chicago on my way back to Michigan (it's currently 3 a.m. here). There are people scattered throughout the terminal, but there is a pattern: they are by the small charging stations.
I found these nice leather chairs with both AC and USB outlets. I plugged it in, turned on some Brian Eno and started to snooze. When I was awoken an hour later by some construction, I realized my phone was not charged. I tried other outlets and it did not work.
The chair was sponsored by Samsung promoting it's new Galaxy S5 phone, which has "ultra power saving mode."
The advertisements for the phone had a group of travelers in an airport huddled around outlets, in bathrooms, corners and floors. At the end, one traveler turns to another and says she is going to charge, the other, who has the Samsung phone, says she doesn't need to: she has the power saving feature.
So it made me laugh in the silent airport: This must be great marketing from Samsung -- or a failure of the airport or just coincidence -- that the charging stations do not work.