And yes, they have a currency exchanger here at IAH. You will take a big hit for the exchange. I have different country currencies, from countries visited but never exchange them here. I use them for future travel. I've dug into the currency bag to pay for cab fares in Mexico for instance. Never a whole lot from each country but I'd rather save the currency and use them later than take a hit on the exchange here. Enter currency exchange KIOSK. I suppose they count on you not wanting to get stuck with anything, therefore willing to part with a cut for them so as not to have a total loss of currency.