It's not unusual for an artist/band to play some of their signature hits far into their career, and it's common for those songs to change a bit over time. Consider Neil Diamond, who has probably a dozen must-play songs for each show. Several of his hits haven't evolved too much over the years, and his voice sounds like it did 45 years ago, no key changes for him! But Sweet Caroline picked up a few changes over the years, where the audience participates in "So good, so good, so good" and "Bah bah baaaah..." And of course Neil encourages and conducts them through those parts.
Even my boss plays several classic hits in each show, but did eventually make a change to the venerable Eat It, which we'd played at every show since late 1983. In 2015, it got the 'unplugged' treatment, actually a musical cover of Clapton's unplugged Layla, so it's really a mashup. But the song is still played... gotta give the fans what they want!
Bermuda