The section you're quoting is about enabling on-call people to have lives without on-call constraints. It's encouraging people to be considerate and cover a colleague's shift if they want to go out and do something, and you're free.
Put another way: recognizing this gets you about as many brownie points as recognizing that eating and shitting gets in the way of your average work day. So zero. It's basic logic and human function.
Scheduling 24h work days will inevitably cause "life to get in the way of work". On-calls commonly take a week or two at a time. Stop de-legitimizing work-life seperation.
That said, if you're on an on-call shift, and something comes up, that's "life getting in the way". And that's fine.
I have separate issues, personally, with how many companies compensate employees for on-call work. But it is an on-call shift, a concept that exists in basically every industry where you're providing a timely service. (plumbers, airline pilots, systems administration...)
Unless you're large enough to implement follow-the-sun, you're going to need someone to cover the evenings.