“ Temple of some malign being invites you warmly and offers help (curing,needed spell etc) for some minor sacrifice . Sacrifices must be everytime bigger to work - up to living inteligent creatures. Maybe you pay some other price,too...”
“ In a society, people who are in a higher postition of authority have a bigger incentive to stay on the right side of the law since the more authority you have, the punishments for criminal activities become much more severe. To the point where the most powerful face defacto death/life sentences for every crime.”
“ A village where everyone goes blind sometime during puberty. What could be causing this? Perhaps something in their diet. Or some malignant gene. How would an entire village where only young childen can see function?”