There are likely a few factors at play here. First and foremost, Kid Rock is a hometown artist, so lots of folks in the 35-54 demo grew up listening to him and remember all sorts of milestones. Second, “All Summer Long” has that “classic” sound that allows it to fit in with the rest of the playlist (thanks to some Warren Zevon and Skynyrd sampling). This is why “All Summer Long” gets played, as opposed to, say, “Lose Yourself”, which probably won’t get played on WOMC for at least another five-ten years.
If you really wanna feel old and depressed, take a look at the playlist for KOLA in Riverside, CA.
http://kola.tunegenie.com/#
The newest song I could find looking at today’s playlist was “Hey Soul Sister” by Train. I was heading into my final semester of college when that one came out. Now I feel old.