If you want to be completely safe, don't ever involve bitcoin transactions with your real name or finances. Purchasing bitcoin with your credit card, Paypal, or bank account is just asking for red flags in the future.
i was asking myself lately about what they do when someone pay in bitcoin to buy something from another country, can they track something like that?
i'm fairly certain that the owner of that online shop, don't need to claim anything to the other country even if he sell item to people outside of his country...but i'm not sure
i think some traces are left behind in this case, and paying directly in bitcoin may not be all that safe from being taced back