We want our salespeople caffeinated. We went to a beverage machine and nobody used it and they resented having their coffee taken away so we brought the coffee back. It was a move made by a sourpuss sales manager who felt that people would sell more if they didn't spend "all their time" at the coffee machine. Sales tanked under her regime and she is no longer with the Company. It was a strikingly negative experience. The coffee part, that is. To be honest, it is true that the 1-bag coffee is pretty darn weak and I'm sympathetic to the multi baggers. However, unless you have a tight budget for coffee, perhaps you can just make some labels or signs to hang on the handles of the pots so people can see what it is they're pouring. If money is to tight for the multi-bag coffee usage, then make people go to you or someone other designated person to get their one bag of coffee per x unit of time. If people want to bring their own to add, that should be ok (but then do make sure there's some way to label the pots).
I really don't think criminalizing it and disciplining people will be effective, especially if you don't have a camera over the coffee maker.
We solved the dairy problem: we don't supply it. I have a small fridge in my office and I keep some 1/2 & 1/2 in it. Cube farm people have super-pasteurized no-refrigeration necessary creamer thingies or they put theirs in the office refrigerator with their name on it. The creamer thingies are real dairy, they just don't need to be in the 'fridge. For those who don't want to figure out the whole logistics thing about moo-juice, well, they can use the powder. Yuck.