I usually don't mind going to work functions on behalf of my job. It's paid, it makes us look good and hey, it's part of my job. Whatever.
What I DON'T like is when I get an e-mail at 3:45 the day before asking me to confirm my attendance at a luncheon the next day. That I've never been invited to, b/c it's for the bosses. I'm not dumb. Not enough bosses signed up to go to the organization luncheon. And I wouldn't mind going, but I think I deserve more than 5 hours request.
So I said no. If they'd even asked the morning or yesterday, I wouldn't have minded. But I'm not going to sit through a luncheon that will have nothing to do with me, my job, my performance, at the last minute. It's rude and presumptive.