I don't think we're too horrendous. But not completely waste free.
I either find sometimes meal plans change and then you're left with ingredients you can't use.
Fruit and veg can sometimes spoil quicker than you anticipate.
I also find it annoying that supermarkets don't a) have more loose veg and b) have the loose veg priced competitively. If I go into Aldi for a courgette and they sell them in a 3 pack for 49p, and you might find they've got loose ones for sale but at 99p each.
I absolutely hate buying bread. Most bread you get maybe 3/4 days out of, and the small loaves tend to be a bit naff, or even still too big.
I slice and freeze and surplus courgettes. Fresh gets used in salads, frozen in sauces.
Bread is strange one.
Anyone who has ever baked bread, knows that it doesn't keep fresh very long. (The obvious exception being rye sourdough.)
Commercial bread however, keeps and keeps and keeps.
Very suspicious and that's enough info to know that anything made with Chorleywood baking process (yippee, industrial bread was a British invention), shouldn't really be called bread at all. Vile stuff.
(To any aspiring bread bakers: most properly proved breads freezes quiet well - even white wheat ones.)
To the OP's question: almost never. It's not hard to cook what won't keep first. Or at least not for me.