Fare evasion?

We were on the number 5 tram, but it broke down.    Everyone had to get off, and we got on the number 2 tram to finish our journey.   We mulled over the dilemma - do we pay another fare?   Since our trip ought only to have involved a single journey, why should we pay another fare when, through no fault of ours, we were obliged to transfer to another tram?

I ventured the opinion that, in Melbourne, it wouldn't have been expected of you to pay again (in the days when each trip involved a separate ticket), so why should it be any different in Belgrade?

Although Rada who was with  us was inclined to agree with me, we took the conservative approach and in fact validated our cards again thus paying another fare at a cost of 60 dinars (just under 70 cents Australian).

I was still brooding about this possibly unnecessary extravagance when, lo and behold, a lady boarded the tram with a device in her hand.  A man near the back door made a hasty exit.   Yes, she was a ticket inspector - the only one we've seen so far in Belgrade.   And, when questioned, she asserted that had we not paid another fare, we would have been liable for a penalty fare.  Not fair, but on reflection, it was worth the 60 dinars each not to have had to have the argument!