As we all know that bitcoin now are being made as a trading pairs to different fiat money all over the world. And we you go round the world having a good vacation on different countries you do not need to bring more fiat or physical money instead bringing gadgets and connecting to internet is enough to get fiat money after it will be traded to local exchange. In this way there is no need for one to bring more physical money as bitcoin could unify all fiat money around the world as trading pairs.
I think it's that easy to use a gadget and trade Bitcoin to their local fiat currency in most of the countries because as we all know. There are already regulations that's been approved to stop anti-money laundering. And you have to need to verify your account first to a certain country because not all country uses the same exchanges, if you know what i mean.