I've been traveling more for work lately (no place exciting, alas), so I've gotten used to eating solo. I'll admit that I have started picking hotels with a restaurant because sometimes I don't want to deal with going out, and hotel restaurants understand solo diners better. But I bring something to read on my tablet and I don't really care what it looks like. I'm a generous tipper, and while I don't drink, I usually have an app or dessert. I did have one place where the hostess was kind of rude, but someone senior to her realized it and corrected. I've never had an issue with waitstaff. Then again, all my trips are in the US.
(Edit) Here's some German food from Hildegard's in Huntsville, AL. The photography is lousy (cell phone and I was sitting outside), but the food was tasty.
