Only with a business explicitly declaring in ToS (or wherever) Bitcoin as fungible am I willing to include it on a whitelist.
But i expect it'll difficult for most business owner to do that explicitly due to various regulation/law. I only expect anonymous group or service which focus on user privacy to do that.
That will definitely be a limitation. I can see how someone could use such a written commitment to Bitcoin fungibility as 'proof that the business endorses and facilitates money laundering' or something along these lines.