I've got'em too...there are 2 schools of thought on this. Some people say they eat coralline, here's what I do know. They reproduce like rabbits, I don't freak over them, but I just get them out when they're easy to reach. Grab the bigger ones with your fingers, suck the small ones up with a turkey baster.
I give them to my kids, they take them to school and give'em to their friends.