(For women, it isn't rude to wear a hat indoors. Think about weddings: it's expected!)
I wasn't referring to woman at a wedding or a funeral or at an indoor horse race function for that matter. It is considered rude for any gender to wear a hat indoors at any other time. People (men or woman) even get kicked out of RSL's for wearing hats! Teenagers get told to take their hats off in school etc.

Chocaholic You can honestly do what you want, as Lady Zaidie said she gets migraines, people don't know why you are wearing your sunnies! So what if people think you are rude, if you don't care what others think then don't let it be an issue to you...Same with talking to people socially at an indoor event when there is no reason to be wearing your sunnies, if you don't have a problem with talking to others without seeing their eyes and don't find it rude than so what if others think it's rude if you have yours on, if you don't care what others think, don't stress yourself about it. For me I don't particularly care what others think but I am aware of these social ettiquettes and I choose to take my hat off and my sunnies off when talking to people because I some people 'will' find it rude.... Each to their own