Demography in Kenya is worse than that of rodents, population is increasing by 50% every 10 years. Sure it has slowed down to only 5.4 kids by family but it results in habitats shrinking for game.
IMO as hyenas are as sex addicted as local people, they have been contrieved to change their table manners toward the most handy preys available, humans. Even more as herbivores tend to be sex depressed and won't breed accordingly, humans are now targeted by hyenas. Proof that hyenas aren't as stupid as one could suppose.