Phones were expensive, in 1960, you’re looking at the equivalent of a $75/mo bill today. The median income then was about $58k 2023 dollars, about 18% less than todays median income.
Also, urban apartment buildings weren’t always wired and while traveling you didn’t always have phones in motels. My grandfather had a bar whose clientele was mostly from a shipyard. When they’d furlough the workers for a retooling or something, he’d close the place and work as musician in a resort town for a few weeks - he’d send a postcard with a pay phone for folks to call at a certain time window.
For me it was that I wasn’t allowed to use the house phone but my girlfriend could use hers so she’d call the number of the pay phone down the street from me so it was free for me and her (but not her parents!)
Also, urban apartment buildings weren’t always wired and while traveling you didn’t always have phones in motels. My grandfather had a bar whose clientele was mostly from a shipyard. When they’d furlough the workers for a retooling or something, he’d close the place and work as musician in a resort town for a few weeks - he’d send a postcard with a pay phone for folks to call at a certain time window.