I remember back in 1993, after my first move to Prague, seeing all these friendly “money changers” who would stand around on Na příkopě at the bottom of Wenceslas Square. As someone walked by they would ask “change money?” and boast they had the best exchange rates around to turn your dollars or pounds or francs into … well, something.
I read in an article on the Radio Praha website that money changers are still around and tourists are still getting ripped off. I don’t know why people take a chance with someone who approaches them off the street when there is a wide selection of ATM machines and banks all over Prague. I guess some tourists feel that the chance of getting a better deal is worth the risk of ending up with a stack of Bulgarian leva.