(The notable exception is Switzerland where, as I know to my cost, a visit to a restaurant should be preceded by a call to your bank manager). But there is much more to this than the cost of holidays. For the UK, the exchange rate is the most important price in the economy. If it goes seriously wrong, then the economy will suffer. It has been going seriously wrong. When the pound is moving in opposite directions against different currencies, it can be difficult to be sure what is going on.