The expected probability of paying a fine vs buying a ticket

The Berlin transportation system is based on trust. Unlike the Dutch one which requires you to check in and out every time you use public transit. 

To enter the bus or the tram in Holland, you have to go through either the driver or the conductor, random checks mostly happen on trains because they’re more expensive.

In Berlin this is not the case. There is no checking in and out. Random checks are rare.

I have been here for five weeks, I met the transportation police only once.

The monthly ticket for most of Berlin costs 80EUR per month. The fine for not having a ticket is 60EUR. Given these two numbers and the probability of meeting the transportation police, what is the expected probability of buying vs not buying a ticket. Which has a higher probability of paying more?

I am not saying that you shouldn’t buy a ticket. I buy my tickets all the time. I am just questioning the reliability of the system, and curious to know the answer.