I would have a serious problem if someone LEFT thier drink IN A RACK (probably ON a server) in both DC's I work in aswell, I do take water in with me a lot of the time tho, 1 to drink and 2 to wipe the equipment faces keep dust our of the machines as best I can. but I have no real problem with people taking soda in with them, I just prefer it be half empty or less. I've lost a server (one of the mail servers for @home/ATTbi/Comcast from coffee, but there's also an understanding at the office and with our vedors that if you break it, you buy it. we docked the guys pay to a livable level for I think it was around 6 months or so, and replaced the server. It was a big deal, but we have 3 other mail servers and just transfered the load over. no downtime (tho our mail servers natoriously suck ass...) and no hard feelings I don't think as much damage would have been done had it not been an almost completely full cup of coffee, and it probably wouldn't have tipped as easily if it were half full or less and thats when I made the suggestion to the staff. but I haven't barred drinks from the DC's
I have however banned food, a lot of food leaves crumbs and other messes that are a pain in the ass to get out from the cracks between the tiles, over time they rot and can stink up the place, so no food is allowed in. there really is no reason for it from what I can see, you want to eat, we have a break room at both location not 15 feet from the DC door. so if I see food in the DC, I give a warning, then take away DC access for two weeks, then terminate them.
these are all known policies and I've never had to enforce them beyond a warning. I don't keep a tally sheet so if its been long enough I've probably forgotten and you just get another. unless I don't like you...

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