I disagree
They are for drinking your drink whilst on the move or on a train. When the cup has been filled to brimming, the slightest bump will cause it to spill, unless of course you keep the lid on and drink through it. If that little hole was meant for a stirrer to stick through, they wouldn't put in that extra pin prick hole to stop a vacuum forming.

But if you are sitting at your desk, yes, take the lid off.
(Big Smurf Brush me daddy-O, Fri 2 May 2008, 12:34, Reply)