The old police lamp is swinging so here's a tale from my early days at Wokingham.
A new kid on the block started a milk round on a new housing development and was potentially taking business from the established Milky. Cue multiple thefts of New Kid's milk from doorsteps in the area.
He was trying to make a new business work so once he'd heard about it he doubled his efforts to be the best. Cue multiple thefts of New Kid's milk and return of now severely off New Kid's milk to those doorsteps.
There was no evidence* to prove who was doing it but there were a couple of suspects from the local milk depot (less than a mile away). Once the depot boss was informed of the alleged shenanigans and realised the implications of this "milk war" on an established, local company's reputation the feud ended.
*CCTV didn't exist nor did social media and I certainly couldn't devote any time to cracking the case.