This is a beautiful story, Mark. When I took a half-year-long hiatus from streaming music last year, the very first album I bought was Man on the Moon. I listened to it when we were kids (we're like the same age btw) and, being a middle schooler, I was too young to understand. Like your experience, Day N Nite at the time was simply a song that they played at festivities, bar mitzvahs--whatever it was--and we'd all have it in the background and not pay attention.
Fast forward to my young adulthood where I was unemployed and had no idea what I was doing with my life. I bought Man on the Moon and listened to the entire record three times in a row that day. I might've listened to it for a few weeks at a time--it resonated with me that much.
Thanks for reminding me of how much I fucking love Kid Cudi and how much he means to me <3