Few more thoughts: I think about how we're planning on eating the foods too, sometimes, when I'm needing to conserve the money and making my choices. If I'm making an egg heavy dish that's mainly for dh (with his intolerances) I get the more expensive eggs. If we're planning on making soft boiled eggs or something similar, where they'll be less cooked - I get the more expensive ones . If I'm making something that isn't egg dominant, I might get the free range but not organic eggs and save a dollar, say if I'm baking them in cookies or something. I don't get the totally conventional cheap eggs because they disagree with all of us. If we're low on cash for groceries and I'm going to want them for my breakfasts (but dh won't really need to eat them) I'll also get the cheaper ones. If I can't afford the cheaper realm of higher quality eggs, we just don't get them.
Same kind of thing with milk - cultured dairy (like cheeses, yogurt, sour cream) rarely bother us so we don't often get those organic unless it's cheaper or only marginally more expensive (less than a dollar more, say). If I know I'll be cooking with the milk in the first place, there are times I've gotten non-organic milk and not even our non-homogonized kind (and save like $2). That's rare, and usually around the holidays when we'll also have guests who will probably drink it up anyway too.
and if I am cooking for others, cookies for school to sell, even Christmas gifts, I don't usually use organic since most people I know do not use organic foods most of the time.