About a year ago on a flight from East Moline to Chicago we had a fruit loop who was "pacing" up and down the isle. He talked to the flight attendant for a little bit that sat in an empty seat on the front row. The flight was only about 1/4 full, but about 6 of us guys all moved toward the front and in the center isle and let the flight attendant know all she had to say was "now!" That dude had all of us freaked out....and we were met at the gate by security who whisked him away!
Good for those people on that flight for doing the right thing!