Folks often forget how difficult it is at times for a singer to remember long and detailed lyrics and sing them with the same genuine whimsical inflections repeatedly.
All of my grandkids can sing along with that song which is a testament to its timeless appeal and popularity.
Local radio station plays it every Thanksgiving at noon. My brother used to go to his buddy's house to listen every year and then he'd come have dinner with the family. We knew he'd get here about 1:30PM. I still listen every year.