This is the norm for nearly every form of transit in Switzerland and Germany, among a few other countries. I use buses and trams daily as well as urban trains a

This is the norm for nearly every form of transit in Switzerland and Germany, among a few other countries. I use buses and trams daily as well as urban trains and seem to be checked every 1-2 months, on average. It works partly because the fines are relatively significant and levels of public trust and integrity are likely more universal, so there are few "Schwarzfahrers" (fare dodgers, literally "black travelers").