Is there an example of a cryptocurrency company that isn't centralized?
You need to use centralized exchanges in order to buy in or cash out. Even small entities trading on platforms like LocalBitcoins need to adhere to KYC laws.
If you were to use cryptocurrency as actual money, I can't see it being cost effective, legal or convenient to only trade with fly-by-night currency exchangers in South America in order to buy and sell cryptocurrency "anonymously".