I like to think of myself as a generous person with pockets of tightness, rather than a tight person with a blind spot in pubs. One of these pockets is around grocery delivery services. You know: you need a green pepper, a gale is blowing outside, so you get some poor kid on a bike to go to the supermarket for you and, by some miracle of modern capitalism, your pepper is only 30p more expensive than it would be normally, as long as you also order ice-cream.

It’s not the money that bugs me, just the underlying Marxist truism – that if some of us refuse to do any of our own menial tasks, others will end up doing all menial tasks for everyone. Plus, we live next door to a supermarket and I’m not even exaggerating, except by a small amount.

Mr Z, on the other hand, loves a grocery service. To give him his right of reply, he would argue that I outsource more menial tasks than he does, to which I would reply … no, wait, I can’t give myself a right to reply to his imaginary reply.

Anyway, we have this argument at least twice a day, so it was only a matter of time before we would have it in a cab and I would want to bring the driver into it. “My husband,” I intoned with a certain amount of seriousness, “really likes Gorillas, while I disapprove.”

“You disapprove of gorillas?” he asked, baffled.

I paused to disambiguate, as they say on Wikipedia.

“This is like that penguin in Japan,” the driver observed, once he had got to the bottom of our beef. “He goes to the fish shop every day and they give him a fish. He has a backpack.” We broke off to find the penguin on the internet. By the time we had watched as Lala, a 10-year-old king penguin, went shopping on his own, we had arrived at our destination.

There was a question mark over who the driver had been agreeing with. According to me, me: if a penguin can go to the shop on his own, a human can buy its own stupid green pepper. According to Mr Z, him. Or rather, how can you argue about a thing like this when a miracle penguin exists?

Genius diplomacy by the driver, in other words: five stars.

• Zoe Williams is a Guardian columnist