Would they also prosecute a person who told them one of their doors was left unlocked after-hours?
A normal person's reaction upon being told "You left your keys in the lock" is usually gratitude, not calling the cops.
EDIT: Is it suspicion? "Hmm...this person found an unlocked door, which means they were clearly trying all the doors. Don't like that. Who knows what else they found but didn't report." Which is understandable, but clearly counter-productive. If the person was a malicious actor, they obviously wouldn't go to the trouble of reporting in the first place.