It takes a week or more depending on the fruit. If that's happening, eat more or buy less. This is such a first-world problem.

I don’t know what you are trying to say, but for clarity: people want to buy the amount of fruit / vegetables they will actually use between the time they buy it and the next time they plan to shop. Not everything they plan to eat / make will necessarily call for the same produce.

Plenty of produce doesn’t last a week from when you buy it and this varies based on where and when you buy it.

As an example, a few apples might last for over a week. A package of raspberries might last 4 days. An avocado that is ripe may last 2 days.

How do you buy less than one piece of fruit? Isn't that what you're arguing against?