Amateur astronomers use them for pointing out objects in the night sky. The green laser picks up moisture in the air and make better pointers than do the red ones.
The little $50 ones throw an impressive beam but apparently are not a risk to eyesight.... I'm not 100% certain on that, it's just what I've been told.
That's probably no consolation, and I'm not attempting to defend the indefensible. I should point out that I neither own one myself nor am I an amateur astronomer
