Yes, they're dangerous is you don't follow safety precautions and I would never allow children to play with them. When children visit we make sure the magnets are not accessible - it's our responsibility to think about others' safety. But it's not the responsibility of the magnet manufacturers, as long as they make it clear that their product can be dangerous (and the vendors I've bought from certainly do). The mere fact that something is dangerous is not grounds for taking it off sale, otherwise we should shut down every gas station and hardware store right now.