Again, to reiterate, if you are a writer and you put in human sacrifice taking place in a starting village, being condoned and implemented by the good-aligned officials of the town, you had better be prepared to address it IN DEPTH in your adventure. Other than the endless winter that's unstoppable by 1st level characters (and isn't really addressed until midway through the adventure), it's the most concerning issue in the Ten Towns.
You're going to go looking for a phantom deer while towns are sacrificing people? You're going to go collecting nature spirits, while the towns are sacrificing people? You're going to go after stolen iron, while the towns are sacrificing people?