There’s no way to raise a human such that their value system cleanly revolves around the one single goal of duplicating a strawberry, and nothing else.
I think you’re misreading Eliezer here. “Duplicate this strawberry” is just a particular task instruction. The value system is “don’t destroy the world as a side effect.”
No, current date labels are generally voluntary and indicate when the manufacturer wants it sold by—beyond that date, the food is usually still safe but not as tasty (and so not as good for brand value). The new rule would (assuming it works as intended) add a second later date that actually means what you and a lot of other people thought the first date was supposed to mean.