bank account and potentially avoid paying TAX on it?
It's considered a trade if you do that as you are using Paypal to convert your Bitcoin into Fiat Currency and not necessarily using their services in order to use your crypto for payments. The conversion it will take place will be considered as your capital gains. You won't really be avoiding any tax here as simply I don't see any loopholes on a straightforward law about your taxes with cryptocurrencies. Keep in mind that since Paypal is a very big company they will be in compliance with various AML laws and they will most likely do everything to avoid and report illicit activities from happening with their services.