Is it not the case that we have, when we were young, when we grew older, when we got jobs have always varied our vocabularies. You had playground language which the teacher couldn't hear (nor your parents). You may have had a language at home which you couldn't use at school. You probably have terms of endearment for your employer which he might prefer not to hear. On the net, if children talk to each other in the terms they use in the playground etc what's the harm. Or am I talking f*****g b******s. Asterisks to protect those of a sensitive nature.
Let the children play.