Bob Seger was an earnest, blue-collar hero who combined the muscle of hard rock with the introspection of folk. It's a sound you can hear in the reflective moments of arena-fillers like Metallica (“Nothing Else Matters”) or Kid Rock (the Sheryl Crow duet “Picture”), or in contemporary country stars like Eric Church and Jason Aldean, who cut their ballads with just the right amount of grit and distorted guitar. Then there's John Mellencamp's “Pink Houses,” the kind of breezy, class-conscious fist-pumper Seger all but invented.