If the chance to get caught is 1/100 and the fine is 10*price of ticket... I myself would feel like an idiot if I bought and stamped tickets. The only valid reason to do so is idealism - you believe that your money goes for a good cause. It's strongly arguable whether in the case of Sofia public transportation the money actually does go for a good cause. Bad management, lack of good ideas, combined with huge corruption mean that you must be an idealist at a very high level in order to do it (to believe that if everyone does what they are supposed to do, the system will work =&gt; at least you do what you are supposed to do).