Unrealistic Character Expectations

One of the things I often find jarring in stories, particularly those with relatively provincial characters, is when these characters seem newly puzzled by the tasks and conditions and social mores of their environment. If the characters have amnesia, or have recently arrived from a radically different setting, that's one thing. But it's quite another when a teenage peasant in psudo-medieval-European Fantasyland, who's never been beyond the edge of their home village, seems shocked and put-upon because their parents ask them to do chores. 
Characters are, in many ways, products of their environment. Their ideas about right and wrong, possible and impossible, and realistic expectations about their future are all formed by the world immediately around them. A character may not like something-- mucking out cow stalls, going to boring meetings, standing over a hot stove for hours-- but they expect it. They know there aren't alternatives, or that the alternatives are worse. Furthermore, they may not have even considered a life where their experience isn't the norm, particularly if they have experienced little to nothing of the larger world and are comparing themselves to people with similar life experiences. 
The upshot of this is that if your character decides they're not going to cooperate with the system, there needs to be a very strong disruption to the status quo. Second, the character isn't going to rebel in the manner of someone from the 21st century. They're going to act like someone from their unique background.