Dear Quentin,

I went for dinner with six friends last weekend, and we each ordered entrees and desserts, and some side orders. One of our group only eats gluten-free food, so he ordered two starters as one meal. We split the bill, and it worked out at $36 each. But our gluten-free friend cried foul, and asked for a separate check to pay $22 for his gluten-free dish. I was outraged — and almost felt physically sick. I kicked my husband under the table, and said under my breath, “Can you believe that?’

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