My MIL is the same way with my stepkids. My 13 year old stepdaughter is forced to wash the dishes and clean up after herself and her brother whenever they stay with her. My stepson is 15 and lays around watching TV and making messes while his sister cleans up after him. One day my stepdaughter objected to her grandmother saying it wasn't fair that she had to do everything and her brother did nothing. My MIL's response was "you are a woman and are going to have to serve your husband one day. He is a man, therefore his woman will take care of him." My stepdaughter said "well grandma, if that is the case, I am never getting married."
She made me laugh that day. Whenever they stay with us over the summer, I make them both clean up after themselves. I want them to be able to take care of themselves and not have to depend on anyone to get them anything. There is nothing wrong with teaching girls to be domestic, so long as it is not taught as a duty but rather as a way to self-sufficiency.