Rotten Tomatoes actually has both ratings, meaning they recognize the limitation you're referring to. In the other, Zootopia has 8.1/10 and The Godfather has 9.2/10, showing that difference in quality.
Also you just aren't the demographic for zootopia. If you have kids then it probably is worth buying and they will watch it many times. There are so many genres of films, it's best to compare within a single genre and not between.