Unless you can completely close down all the sites stealing content, you have no options if you want to stay in business. You have to win back the customers.
Closing them down is a nice dream, but what if they started to buy content. Am I not allowed to sell to them to support others or will others buy from me to stop me selling to ex thieves?
Content is very cheap because sponsors forced down prices. You might shut down all the sites stealing, but then they would simply buy and sell for 25 cents a movie. 1000 sales at 25 cents = $250. Try to close them down and they will sue you.
Keep kidding yourself the problem is stolen content.
Now tell me the people looking at the stolen content would not buy 25 cents scenes but would buy $30 memberships.