Is that really true? Are people actually calling them up and begging them to play Nat King Cole and Andy Williams when it's still 80 degrees outside?
I've lost count of how many radio formats launched with liners proclaiming it to be "the radio station YOU ASKED FOR!" -- only for it to bomb in the ratings and flip to something else in short order.
And so-called "all-request" shows are almost never actually all-request, because if they were, they'd be playing the same burned-out songs over and over again. Years ago I called one to request a song, and the DJ yelled at me, saying he was tired of people calling to request that song every week, and he wasn't going to play it again for a while.