I'll tell you what's in it for me when I stay at a session after my character dies:
1. Social Companionship: I game with friends. I like visiting them every week; we have plenty of side conversations and digressions in our games because this is social time for us to hang out while doing an enjoyable shared activity.
2. Following the Storyline: Usually a good game is driven by a strong narrative that is enjoyable in its own right, all the more so because my character has contributed to chain of events leading to the current situation. Often there is information about the world or larger plot that you can learn when your character is doing nothing.
3. Watching Good Players Play: The people I game with are good at playing D&D; that means they come up with witty, entertaining things for their characters to say. The figure out what is going on and make plans. They fight strategically and dramatically. I like watching the game being player well, even if I'm just a spectator.
4. Taking Turns: Player on-screen time balances out in the end; if I tolerate some subset of the party taking centre stage for one episode, there is a greater chance that if I need or want to do this in a future episode, my fellow players will be accommodating.