Three problems with these rubber nuggets: The nuggets will naturally get scattered and tracked outside of the playground and will end up washed into sewer drains - thus causing damage to infrastructure and polluting our waters. Secondly, small children will probably enjoy putting the spongy little rubber nuggets into their mouths (much more so than a woodchip) - posing a choking hazard and a potential disease transmitter. Lastly, on more of an ideological level, children should learn from their experiences that it is painful to fall down - a bed of rubber nuggets underfoot does not convey this message.