I was taught eggs went into the Meat category (which was basically Protein, and they sort-of handwaved beans). I have more than once run into people who were taught eggs were Dairy. For no reason I can figure. I once, in seventh grade, got into an argument with a girl who lived near my grandparents' house over this very subject: she did not respond well to my clearly correct argument that Dairy came from cows, so eggs weren't Dairy.
Nowadays, I point out that if it didn't start out with lactose, it's not dairy, but I did have a husband who shall remain unidentified once offer me Lactaid with eggs, as he was reverting back to his primary-school programming that eggs went into the dairy category.
Hey, he made me the eggs! I am not complaining!
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