I've encountered the "loose outlet syndrome" in hotels. I suspect that it's due to vacuum cleaners plugged into them every day and having the cables yanked out. Oh, and the use of cheap outlets, too, since "nobody uses them."

While it's not much help on an airplane, where I usually have to get down on my knees with a flashlight to even find the outlet, at a hotel, I'll ask for a long extension cord. Most will provide one, though often they misunderstand and send up a multi-outlet strip with about a 4 foot cable. Given about 10 feet of extension cord, I can usually find an outlet that will hold a plug and get the socket to where I want to use it. I've started carrying a cheap extension cord in my computer bag just to be sure.

The USB power adapter that I carry has two outlets. On occasion when on a plane, I've offered the second usb outlet to a seat mate having trouble with an AC outlet.