The sort of people who work in areas that interface with travellers/tourists seem to include among them a particularly high proportion of 'chancers'. This is the case in every single country on the planet - they see an opportunity in exploiting those who come in and are unfamiliar with their new surroundings. Thus, depending on the country, you can expect baggage handlers, immigration staff, customs officials, taxi drivers, bar staff, etc., etc. to include people 'on the make'. What I have no time for is those who pander to these sorts and let them have their way: this will inevitably breed stories of easy money, thus escalating the situation. The worst I have ever seem in this regard was a European passing ahead of me through an African airport. He literally put his hand in his pocket and handed over a note at every point of contact with staff of any kind, from check-in right through security, passport control and to the departure gate where our paths separated. It is entirely natural that each and every person I then encountered asked me 'What do you have for me'. Mind you, an airport shuttle bus driver once demanded a tip from me as I got off at Washington Dulles (I was the only passenger) - so much for civilisation.