Why attend scientific meetings?

Attending scientific meetings is not a cheap enterprise. Neither in grant dollars (that might be better spent on supplies) nor in time (that might be better spent doing an experiment or writing up a paper). So why do it? Well, the overt reasons are pretty simple. First, to find out what other people in your field are working on and thinking about. Second, to tell the other people in your field what you are working on and thinking about.
This is the selfless and team-oriented aspect of science, the goal being to save everyone a little time and effort. Time that might be wasted between collecting the data and publishing the paper (conference presentations are often works-in-progress) during which the field would otherwise be ignorant of the results. Time that might be wasted going off in the wrong direction (your conference presentations solicit ideas and advice from your peers) or failing to pursue the most promising new avenues.
I’ve been pondering a slightly more….motivational aspect.