I don't think the delivery person has any influence on your produce - at least in the UK, pickers and delivery people are separate jobs, and I can't imagine it any different in any efficient organization. (Also nobody I knows tips for delivered groceries in the UK - the delivery charge is supposed to pay for the delivery. This might be different in the US like all things tipping.)

Responding to both comments - here in the US (at least in my city), when you place a grocery order on Instacart it only gets accepted once the shopper chooses to accept it. The higher your tip, the more likely they will accept it faster. The app then shows you a photo of the person who's shopping for you, and they will text you as they shop if something is missing. They then check out, get in their car and drive to your house, and that's the same person who shows up at the door. I definitely think the tip level makes a difference to the quality of selection you get, but also it seems like it would be very rude not to tip well. However, I tip 20% (which is standard in a restaurant) and I know a lot of people who only tip 10% on groceries. There are probably people who tip nothing. No one I talk to is quite sure what to do, because it's "new territory", just like we didn't know what to do once restaurants became take-out only for covid but the workers still had to be there, and weren't making any tips. I decided to just continue to tip 20% even for take-out.

Before I lived in Europe for a few years, I had to be physically restrained from tipping too extravagantly when I would be there.

It's because in the US we don't have much of a social safety network. Tips are like the libertarian version of social welfare. When I was a waiter in New York, for years, the hourly wage from the restaurant was $0.00 + taxes on whatever tips you made. There is no minimum wage for waiters. Waiters bought their own uniforms and their only income is on tips. And we would have Europeans come and drink coffee at a table for a few hours and leave no tip; they didn't understand that we made nothing unless they tipped. As it is now with the delivery services, the pickers and drivers are making the bare minimum; it's incumbent on us to tip them well. We understand that the service doesn't provide enough for them to live.

As a Scandinavian person living almost wholly outside "tipping culture", that worry just sounds bizarre.

Here, if you order food for home delivery from the major grocery chains, the order is not packed by the driver, and fresh produce is typically in smaller paper bags inside the large outer bag (the ones the driver carries from the truck).

There is no tipping of the driver, who just puts down the bags outside our front door.