• Hat Rule Number One: In the evening, a woman may wear a hat in a restaurant if she is wearing street clothes. (Women are not in “street clothes” whenever they are dressed for a cocktail party or a formal "black tie" event. Jogging suits are not "street clothes" for anyone over 40 or 50 and no hat in the world will help.)
• Hat Rule Number One Again: Because so many sites get the hats-in-restaurants issue wrong, I want to reemphasize correct etiquette with a quote from Gary Warth at VillageHatShop.com, "Women should not remove hats that go with dinner suits or dinner dresses throughout the evening."
The rules of etiquette confuse people because men must remove their hats in a restaurant or at a table. On the other hand, only Ronald McDonald would consider a hamburger joint to be a restaurant, so that would be a gray area for men's hats.