the monsters don't have society system, they don't group up to work together, they don't do fair work, they just do whatever they want and no one complains about that (except our MC but more curious than complain), and when asked about it, they are confused which lead me to believe that they don't think about it at all and consider that as normal > They are not smart enough to see other people as food source so at most when food gets scarce, they will most likely eat the one that died instead of the living ( in the worm chapter it showed that they only consider the ones that can't talk as food and it seems like they only eat the dead out of respect instead as food as showed in the Village of Death chapter, when our MC is being asked to eat the two lizards and Susuki when they die, he said no which caused Susuki to feel sad, even though the other two are fine and said because they are grow up and they understand culture different). In addition I don't think they are smart enough to plot out and kill someone for food or dumb enough to wait for food get scarce, they will move out as soon as they see the sign of it, although if nature is against them then they are as good as dead but I don't think the author will go there, the manga is meant to show the monsters' culture and such