He stops at an Italian ice stand in the park—the best in the city, he says—and you refuse to get any so he has to eat alone while walking with you. Or he takes you to a restaurant that's world famous for its seafood and you order a salad, everything on the side. Or just as bad, you order several of everything, barely touch more than a modest portion, and doggy-bag the rest for later. He's either completely ticked off that you had no interest in sharing and appreciating his taste in food or wonders if you just used him for a week's worth of gourmet groceries.
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He'll either end up making comments or asking probing questions about your eating habits that you'll find make you uncomfortable and defensive. He'll just give up. The odds that he'll ever try to share his love of food (which is right up there with his love of sex, sports, and sleep): spoiled.
Bottom line on spoilers: Don't do them.
And don't let them be done to you.