Underage users

Can someone explain to me why Youtube/Facebook/MySpace/Bebo/etc allow a child of the age of 11 years old to create an account on their sites without even attempting to verify their age?

I realise it states to put in a DOB, but most of these kids put in a fake one. Why not FORCE verification on the user by way of credit card, etc. If a kid wants an account their parents require a c/card to be verified.

>>11
Exactly. Internet censorship in the US will only get as far as ACTA, which is just corporations whining about people pirating. So really the only thing censored would be torrents with copyrighted material. It still isn't a good thing, though.