That's the EXCUSE. The real REASON is to be able to track and CONTROL what you spend YOUR MONEY on. They will have control over what you can buy and who you can buy from. If you don't agree with that, I will assume you are connected to, or part of BIG BROTHER. They are even likely to have a transaction fee as another taxation avenue.
That was shown to be possible and probable in Canada. The proof is there for all to see.
