For me, filler tracks are:
1. Tracks that aren't performed live on the tour (too soon to tell in this case)
2. The absolute most forgettable song(s) on the album.
Bad Kids
Highway Unicorn
Heavy Metal Lover
Electric Chapel
+ the 3 bonus tracks.. but they are bonus, so they are sorta immune to being called filler, cos they are standard album rejects anyway.
forgot about Americano. not sure what that song is doing on the album. it's just so random.