Why not educate them a bit about being open to what a cinematic experience can also be other than a fast pace passive experience. Talk about the space for stretching reality's metaphorical and narrative qualities for stories to become cinematic in the case of the dog shit / also if things don't match your expectations of reality that doesn't mean its unrealistic. My mom and I would finish films, and conversation used to be about "I didn't like the ending" or "why did this happen to this person" or "what was the lesson here?". We talked through these things (it took time and caring) and now she also sees films a bit more as a world to be emerged in and appreciate as such. Not a morality lesson, but a journey, a way of seeing and entering complex characters and situations. I've heard Cuaron describe this film in particular as he would describe life, "nothing but a shared experience of moments", not a Bible's study group or a morality trip. It just wasn't conceived like that. I told my mom, beforehand and we have been developing this type of a relationship with cinema together cause I want her to be able to appreciate my work in the future, to focus and appreciate other aspects, to enjoy and engage in feeling with the film, to pay attention to sound among other things and stop trying to figure out or compile a film into what is trying to say or not say. We all learn how to appreciate different aspects of life be it food, literature, engineering, poetry or whatever discipline, by paying attention to the ways we engage with these things. This idea of a passive viewer waiting for a lesson to be taught is saturated at this point and a very limiting experience in regards to what cinema has to offer, they are missing out on so much if that's their focus. Also, my mom was a child at the historical period of the film, she was reminded of the bed she used to sleep in, one very similar to the children's bed, she was singing some of the songs, and she enjoyed those moments too.