I don’t think that’s a toy example to illustrate a philosophical concept of general interest. It’s somewhat messy/complex (rather than toy) because it’s just a modified version of the Popper/Hume issue. It looks parochial to me; I don’t see why to talk about it other than because you’re trying to criticize a particular thing Popper said.
If someone meant a statement as a general way things work – but allowing for exceptions, not as a strict universal rule – then criticism like Popper’s/Hopper’s would be wrong. But if they said or meant something more like “bread (given proper preparation and some other conditions) always nourishes humans (given current biology) in all contexts with no exceptions” then they’d be wrong. I imagine we agree on this.
I remain unclear on what, if anything, you disagree with me/CF about.