That's fair, but also just because they don't perform the new music as much doesn't mean they don't want to. I feel like these bands very much do want to play the new music, they just have these huge fan bases that don't want them to. I've never seen so many people leave the concert viewing area to the bathrooms/vendors as I did in 2003 when I first saw Def Leppard and they played some of their new music. It was like a mass exodus that clearly the band sees too (and since then, they've hardly played new songs and just play the same hits).
Personally, i would have loved to see DL at their Vegas residency, it seems like the only time they really played deep cuts and I believe they do like to and do want to do those songs, they just can't do that and continue to play arenas and stadiums because they'll lose all those older fans.