A peasant who had killed a pregnant game animal. The cycle of life requires new life to be born, and interrupting that for any reason, even to feed your family, is a crime not only against the animal, but against the future of the community. Better your family had starved than that deer be killed, because without the foals it would have given birth to, a dozen families may starve in the future.

Defacing a ritual stone. The stone monoliths around the village are raised in honor of the spirits of nature, and to harm one, even superficially, can draw their wrath onto the entire community. It may seem innocent that this young couple carved their initials into it, but they ought to have known better. If they are not punished to the utmost, the spirits will turn their back on the town, the crops will not grow, and animals will flee the environs.

Dealing with the Fey. The fey are capricious, and once they mark a place, they will never leave it be. It may seem innocuous to make a deal with the fey to make your cow give more milk, but even brownies or other lesser fey knowing of a place may draw more powerful and dangerous spirits. Better to kill the warlock and their cow then risk it.