It's not just scams. There could be many reasons why a bank would freeze "your" money. There have been many cases, some recent, and some recently in developed/first world countries without due process, of governments telling banks to freeze someone's money because you did something the government didn't like.

If you give your money away, then it's not really your money. If the other person doesn't given it back, are you going to force them to? Are you going to tell the regional controller of force to them them to do so? What if it's that entity that doesn't like you?