The counter
was not unusual in European telephones. Until deregulation (which, to everyone's shock actually worked!), our phone companies in Europe charged prices per "Einheit" (Unit) that you wouldn't believe.
Well, yeah, if you have an American cell phone account, you would believe it.
The counter whirred around at a sickening speed when my mom would call my dad from Germany in the 1980's. Her flight over would cost about 1500$, the phone bill would be about 2000$ per stay.
It was not unusual for many people to share a telephone and with the counter, you could "divi" up the costs when the bill came - everybody just entered their share on a list.
Was fun in my house - my roommate at the end of the month would have like, four phone units and I would have 3,000.
The pulse to trigger the counter used to cost one DM extra in Germany, after the Euro conversion, one Euro. Everything was doubled in price when we switched currencies, although everyone denied it hotly. After it was too late to do anything about it, the government finally admitted it.
Sort of like when Republicans say: "Read my lips: I will not raise taxes". Everybody believes them, votes for them 'cause the g'dam Democrats jus' raise taxes...then the Republicans raise taxes sure as shit the moment they can. But the trick works every time, sure as shootin' - just ask my redneck relations.