Ha ha... I think the Marshal was clever: if those service calls were “free”, i.e. included into the monthly charge from Bell System for all the lamps, buzzers, buttons, etc. etc. Then you don’t pay more for each extra call.

Probably this was his logic: if we pay these guys so much for each lamp in my Call Director, I want them to work like hell and check the lamps/speakerphone/etc. every month.

Otherwise his secretary could be instructed “to fix” the speakerphone for her boss.