They patted down my wife and checked for explosives because she was in a wheelchair. How many white grandmas in wheelchairs have blown up buildings or planes? None.
Here's a true "Grandmother Hassled at the Airport" story as related by my daugher who recently flew home from college for Christmas. An elderly woman had a Christmas-scene snow globe in her carry-on. You know, that glass or probably plastic globe about the size of a baseball you shake and fake snow falls over a wintry landscape. It was a gift for someone. She had to leave it at security. They identified this old lady with a snow globe as a threat!