instead of passively throwing it out, how about you ASK the person whose item it is if you can or if they will.
Nobody labels their milk. If they do it's a single initial (how am I supposed to know who C is in an office building with nearly 100 people?) or maybe a first name (we have about 5 Chris'). This is milk that has gone solid, or is reeking the place out and when there are literally 20 or 30 single pints of milk in the fridge, anything that is out of date is a health hazard (more I'd say than wrapped raw meat in date - how do the rest of you keep meat at home? A separate fridge?)
Or maybe I should try and borrow a tea trolley, put all the 10-15 out of date pints of milk and 5-10 other out of date foods on it, and go round every single office and find every person who works in the building and ask them individually if it was their food and whether they were planning on throwing it out that day as it is now out of date and smelling the place up? Of course, some people work part time or work from home some days so I'd have to repeat this every morning and every afternoon for a week to locate the owners of some items.
Frusso I know some people do that which is why labelling something explicitly means I (and the cleaners) will leave it alone. Unless it says "taken out of freezer on 3rd May" and it's the 4th of May but the milk carton reeks to high heaven.