Setlist here and setlist there

Today there has been a lot of talk between Crashdïet fans about setlists. The guys just finshed their small tour in Australia (so happy and proud that they made it all the way there) and people are curious to know which songs they played. I've honestly never really understood the thing about setlists. I mean yeah, it's fun to hear if the band played a song that they usually don't perform live. For example, Crashdïet added "Save her" to the setlist on their last acoustic gig in Australia. That is a beautiful and at the same time tragic song that always goes straight into my heart, but I've actually never seen them perform it live. There are just too many other Crash-classics that needs to be put first on the list I guess.

But I'm really not that kind of girl who stays longer after a gig to get my hands on the setlist (the piece of paper that all bands write the order of the songs on, in case that they forget it). I just don't see the point in saving a piece of paper that often is pretty dirty cause people has stepped on it. Maybe it's the historical aspect of why people want it so much? The fact that this setlist was used on this night and this night only.
Or maybe the important thing is that the artists have touched that piece of paper? I get the point if you get it signed, but other then that I'm lost...
If anyone feel like explaining it to me, then please do because I'm curious :)

If postcards looked like this I bet people would send em all day long, just for the fun of it ;)