Before being repriced as just a tourist facility, San Francisco cablecars used Fare Registers, as they had done for maybe a century. Roving conductors (who also assist with handbrakes on steep descents), fares are collected but no tickets. A rod with several handles in the roof is pulled by the conductor for each fare, a large clock mechanism shows the number of fares collected and there is a loud bell when pulled, along with noise from the mechanism itself! Another rod with smaller handles does child half fares. The traditional hanging on the footboards outside was no deterrent to being asked for fares as the street flashed along under your feet.
As we are doing ticketless cash sales in other countries, I'll also mention the free enterprise "Marshrutka" minibuses which sprang up in Eastern Europe, principally Russia but some other countries, and which made quite a dent in the official urban transport patronage. Using local Ford Transit-lookalike vehicles, about 15 seats, route description and flat fare pasted to a side window, they stopped when hailed, you just slide the side door open and took a seat. Flat fare pasted on the window, say 70 Rubles, so take out a 100 Ruble note and give it to the passenger ahead. They know what to do and pass it on forward, eventually gets to the driver who had a basket alongside to put it in. Minute or two later the 30 rubles change makes its way back hand-to hand for you. All done completely honourably, no tickets, no mixups. Another passenger boards, sits behind you, next thing you know a hand appears over your shoulder with 100 R note in it. You know what to do now ...