Here is another video that talks about why we do Agile. These two (this one and the one just posted) were the top two vote getters (from a perhaps somewhat biased large audience) at the Agile 2007 conference.
It's a bit serious, I think.
Perhaps a bit overdrawn, but I do think developers have a better life with Agile.
My view is that in Agile, we are trying to make everyone's life better: customers, managers, team members, business guys, end-users, our own families. One would hope, that after all those people are helped, that society more generally would be better.