The lights look green because the picture was taken under tungsten studio lighting in front of a white background. In this situation, the film (or white balance) has to be set up to compensate for the light source to make sure you don't get a weird color cast. There is special studio film for use under tungsten lights, or if it was taken with a digital camera the white balance could be set for the tungsten lamps. Turning on the xenon headlights of the car add another light source of different color temperature. You ever notice how fluorescent lights show up green in photos? Xenon lamps have a similar color temperature to fluorescent lights, so in this picture which is balanced for the color temperature of the prevailing tungsten lighting, the xenon lights appear green.