Also keep in mind that the camera could have been on a low-light setting, (CCD sensitivity, the iris, or both) overexposing the shot, and that the actual "daylight" or the sky would have looked quite dim to our eyes were we actually there, so the beam wouldn't have been competing with full-blown daylight after all, and of course the camera would be much more sensitive to the beam as well.
Also, red is at one end of the bell-curve for human vision sensitivity, but camera film and CCD's don't have that limitation also enhancing the laser's visibility.