if you get into the content business its YOUR business to protect your copyright. NO ONE ELSE'S.
As Kimmy says, its a courtesy for a sponsor to do this.
if someone emails me about a copyright infringment, how the hell would I know if it was valid or not (I don't spend my day looking at porn)
If I cancel their account do I pay them what's owed or not? If not, will the content provider pay my court costs when the webmaster accuses me of stealing his money?
If I pay him and cancel his account, what is the point?
If you're in the content business, don't demand that ANYONE else do your job for you.
period.
how often do sponsors ask content providers to revoke licenses of guys cheating them?
get it?