If you catch somebody doing something it's easy to catch them doing, it's a safe bet they're also stealing in ways that are much harder to see.
My supervisor at one job would routinely steal food out of the fridge but he was also stealing from the company in the form of turning in hours he wasn't working (intentionally riding the clock while in overtime, well past 40 hours for the week) and looking at porn while on the clock.
Theft is theft is theft as far as I'm concerned, and what he was doing was no different from walking into a store and sticking a gun in the cashier's face.
I complained about it but nothing was done. In fact the CEO and the vice presidents started treating me like I was the one with the problem...