Chetwin said: "If it's annoying on Saturday, it's probably doubly so on Sunday." The best thing to do was to be polite, firm, and shut the door.
Though it might be irritating, there was little recourse - a note on the letterbox would probably accomplish little, she said.
But legislation due to pass in Parliament this year will toughen rules around door-to-door sales to guarantee cancellation rights for 10 days and restrict solicitations to "reasonable hours" - though this was unlikely to rule out Sunday calls altogether.
Megan Lacy, the head of call-centre consultancy Lacy Consulting, said Kiwis were unique in their aversion to Sunday sales calls and it should be respected. She advised local businesses to avoid direct marketing on Sundays.
"Sundays are off-limits for some businesses - it's family time."
Sunday calls would be counterproductive in making businesses attractive. People would feel they were being treated as part of a quota or sales target, she said.
"It's how Kiwis work and think. You wouldn't do it to Kiwis on Sundays because you're just not going to get a response, and it's not worth putting staff on.
"That's the Kiwi uniqueness: 'You encroach on my time and I'll remember that and I won't use you'."
New Zealand businesses ought to make a point of difference against global corporates by showing personal consideration.
"In larger centres [abroad], it's more of a free-for-all, with call centres pumping out calls for volume. And to be honest, the standards are coming back to New Zealand. Right now it's about customer experience ... and calls on Sunday aren't going to help."
Vodafone said its sales team worked seven days a week, "as is the case with other service businesses".
Telecom had a different policy. "We would never do door-to-door sales on a Sunday," its spokeswoman said.
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