Because it's always good to consider your own mortality whilst eating a sandwich.

So, you've popped your clogs and are making your way to the great post-gig party in the sky. Your loved ones and nearest and dearest are all weeping in the aisles of the local church/synagogue/mosque/designated humanist building of your choice: So what songs do you play? You can have three - after that, they'll start to get bored and leave.