A few years ago I witnessed this phenomenon firsthand. Paul McCartney (and Heather Mills - his wife at the time) were walking down 57th Street and passed me. The excited couple in front of me then tried to explain to their kids who Paul McCartney was. "He was a Beatle!", they kept saying - which obviously meant nothing to the unimpressed children.
For my part, it WAS pretty cool to see a living legend walking around the streets of NYC.
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