@Elena I was thinking about this myself. And I realized that when I take the metro I always ride with a ticket. It's easy.  I have an electronic card and you can put lots of rides on all at the same time.  While a month or a three month pass is convenient, for those of us who don't take the bus every day it's not necessarily the best option and paper tickets seem clunky and antiquated. But I think that what really compounds the problem is the low price of the fine. Yesterday I was totally fine handing over 10leva.  50 leva? That would have been a different story and a serious fine like that probably would motivate me to stamp my ticket for every ride.