[Retric]

You don't exchange your debit card during the transaction.

It's perfectly legal to map USD > token and exhange that token. It's legal to create a token that you will map back to cash. It's not ok to accept other peoples tokens that does not represent actual money that exists.

Travelers checks are an example of the first kind of token. Poker chips are an example of the second kind of token.

You can accept a Travelers check from someone else. But you can't operate a business that accepts Poker chip's from someone else.