VISA, mastercard is bank institution, paypal also acts like bank( I don't use paypal, so I can't say about that strong), so there are two different things. They have special law power issued by government,
I do not believe you have even spoken to a lawyer about this. Their "special power" is called "law", and it applies to everyone. No special powers involved.
when you agree to use their services, you sign on agreement (that they can block you money, if they see any problems and etc.),
It doesn't need to be in an agreement when it is regulated by law. Aiding in the trade of stolen money or other goods in my country will get you three years in prison. The bank mangers don't want to spend their life in prison, so any stolen money are immediately locked.
To sturle : it's strange for me your strong opinion about all this, without knowing everything.
I obviously know more than you pretend to remember.