I will keep saying this until I am blue in the face. Fiat and Bitcoin will not mix, the banks will never allow it because it will make them obsolete. What part of that do people not understand? Bitcoin was designed to replace the fiat system and here we have people trying to integrate the two, LOL. It will not happen!!!! Make no mistake, this will be an all out war between the banking system and Bitcoin.
The problem with this is that companies with products cannot accept bitcoin without a way for them to pay for the products they sell. There HAS to be a gateway for users of crypto-currencies to facilitate their real-world dollar values into existence. If you close off FIAT <--> CRYPTO then how do the supporters of the crypto and those who accept crypto in lieu of 'fiat based payments' for their products or services, then how do you expect those people to deliver their services or products? The ultimate solution would be for their suppliers to accept crypto as well (but then again, you have just moved the necessity of conversion from the 'middle man' to the supply point. Electricity costs fiat - you cannot pay to operate a factory in crypto without there being a method for the crypto to have fiat leverage.
While your concept is everything that cryprocurrency stands for, you have to consider that until the MAJORITY of suppliers, vendors, and the likes move away from FIAT and over to crypto, there is NO conceivable way that crypto will ever have value other than the data space it consumes for the ledger.
I run several FIAT based businesses - I lease managed/unmanaged dedicated servers (no VPS), I do web design and site building, among many other things IT related. I would love to accept crypto - but I cannot without a method to convert into fiat so I can pay my vendors and suppliers. If they accepted it, then they have to have a method. You can't pay for your basic necessities of a business without fiat of some form. Eventually, the money runs out.