They brew coffee where I work, but if you want dairy additives for it you're on your own. Fair enough. It is a nonprofit, after all.
I don't like to drink my coffee black, so I buy a pint of half-and-half each week and keep it in the office fridge. I used to simply write my name across the top of the carton, but I guess that wasn't a clear enough indication of ownership because someone decided it was acceptable to take from me on a regular basis.
I know about the thievery because I have just the right amount of OCD in my personality to put the carton back in the fridge in the same position each time I use it. When I return and find it turned around, or askew, or notice that there's less liquid in it, it's clear that someone else has been using it. On one occasion, the offender even had the audacity to leave the smallest bit of liquid behind in an almost-empty carton, like some twisted gesture of sharing.
Honestly, how lazy or cheap do you have to be to do this on a continual basis? I can let it go if it happens once in a while. Heck, people can even have some if they just ask me. But this person did not have the decency to do that. So I tried sabotaging them.
To be fair, I had already sent out an annoyed email to all of my coworkers complaining about the thieving. The result was temporary, at best. Any sense of guilt or remorse on their part didn't last very long, and the stealing eventually resumed.
I bought a "decoy" carton and experimented with extra ingredients. Hey, it's my property and my prerogative to put in it whatever I like. If someone happened to take some without authorization and got an unpleasant surprise in their cup, it served them right for doing something they shouldn't have. With my office being the size that it is, though, I could only narrow down a list of suspects but was unable to pinpoint exactly who the culprit was. I wasn't even sure if the miscreant had gotten a taste of my special mix, although I sincerely hoped so.
Revenge plot abandoned, I decided to institute a "triple-locking mechanism" consisting of three binder clips clamped over a sticky note with my name written on it that's folded over the carton top. I figured the less convenient it was to help themselves, the better the chances that a person wouldn't bother. My method appeared fairly effective for a stretch of time, as the crookery seemed to decline.
Recently, however, the perpetrator got brave or desperate and breached my security system. In frustration, I resorted to adding the note seen below.
I'm sure it'll only be a matter of time before the bandit strikes again. I suspect that any notes I post are but temporary deterrents. I could stop being so stubborn about all of this and just use another container to store my stuff, but I really hate having to maneuver around someone else's bad behavior.
And now there is actually a more intriguing question on my mind: Are the half-and-half thief and the individual who has been taking leftover food from multiple coworkers one and the same? Hmm.