At first, I went and left as quickly as possible. Now that I am familiar with the people around me, and more comfortable just talking to them on an everyday basis, I usually stay at least 20-30 minutes after the meeting has ended.
The people at meetings have become my good friends. And the conversation after the meeting isn't usually anything too deep or meaningful, unless one of us needs it to be. But, generally, I do stay without even realizing it now.