Street Chess

Some people are so good at playing chess. But what good does it do if they don't have a job and don't make money out of it? So some of them have this idea of putting the challenge onto the street. They challenge any passers-by who feel they are good enough at the game to beat them in a pre-determined number of moves. Those who are interested to meet their challenge can put a bet and play. The winner takes the money. A fair game?