From the game master perspective, if you don’t put in the time to create a background why should they do much for you? What is the currency here? They don’t run the game altruistically. What is in it for them. If you want to be entertained for a few hours, socialize and go home, it is easier to go to lunch. The players need to interact to bring it alive. If they don’t, then the game master only needs to line up monsters for you to kill and doll out treasure. Is that fun?
You need to make your character worth your GMs time. Why are they gallant or mean etc? If you don’t, the GM is under no obligation to go out of her way to make the game work for you – she’ll be too busy with other players who created characters that have a reason to participate.