Do you have a healthy retirement plan/investments already? If you do, then it's probably a waste of your time, or a waste of a good meal having to listen to some guy or gal drone on and on.
On the other hand, I had a co-worker invite me to one 12 years ago that turned out to be a good move. I weathered the Great Recession with far less losses than most people, and my Return On Investment is triple what I was doing before. And I got a decent Chinese lunch out of it.
Just keep in mind that any investment can vanish either due to market fluctuations, or government stupidity/malice. But it's like the Super Bowl, you'll never win if you don't play the game.