Hi and welcome to ADT. This topic has been discussed at length in some other threads already so I'll refer you to those where you can continue the discussion. But I will provide this bit of info: most of the popular tube sites are owned by Manwin, the company that also owns Brazzers, Mofos, Digital Playground, Reality Kings, and probably several other porn studios. They do get in trouble, but nothing has stuck so far.
Now, please see these:
How to Stop the Tube Sites
How to Stop Tube Sites Part Deux
Tube Sites
Vivid Entertainment Files Suit Against ICG
And some that are maybe 90% related but not 100%:
Porn Piracy gets personal... - but note the conclusion of that particular case
Curious about industry's business future.
And this mammoth thread: Porn is a dying industry. - lots of interesting discussion here.

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