40 minutes is roughly how long we sat at a Friendly's in Williamsburg (VA) that we'd eaten at a few times before. We finally left, for good, but first stopped at the register to calmly explain that we'd gotten there just before a busload of high school girls, and waited while they greeted them, got them beverages, took their orders, got their food, and we got no attention of any kind. "And we would have left an actual tip," I added.