Scooby Doo and the Happy Valley 5 Colleges in MA

Is it true? I just heard that the Scooby Doo main characters were created by the inspiration of the 5 colleges and universities in the Happy Valley of Massachusetts. I thought it was a good match, but is it just a coincidence like the Dark Side of the Moon and the Wizard of Oz? Was it about the 1960s Happy Valley with a puff of smoke rising out of the Mystery Machine Van every time they opened the door? Well, Snopes, and other urban legend websites says coincidence, and the characters were not inspired by the 5 colleges, but I like the coincidence. Here is how it goes:

Scooby Doo - the party animal of UMass
Shaggy - the Hampshire College guy who always has the munchies
Freddie - the Amherst College smart and preppy pretty boy
Velma - the braniac turtle neck wearing Smith College woman
Daphne - the rich, sweet, pristine Mt. Holyoke College girl

Those of you who went to school in the MA Happy Valley have to admit there is a coincidence here for the stereotypes of these schools. I admit it, and I kind of like it.