It’s not blackmail if it’s a point of contract you agreed to.
I admit the BCP’s T&Cs are a little murky, but for example, Bet365 has a 5-player rule in the first month. If you bring 4 players you won’t get paid, if you bring 6 players you get paid. If any of the parties break the contract, the other party has the right to do the same.
Online gambling is business, just like any other. The same way you expect a casino to work, the casino expects you to work. I am not justifying only BCP, but any aff program which has the balls to put out a contract.
And yes, I would like to see an industry standad in T&Cs, where both parties are required to do something. This way when one aff program breaks the T&C everyone could see the facts.