I mean, it appeared to have only the single gradeschool for Beav and single high school for Wally -yet it had several large office buildings as well as a stadium and even a television station. Were all these folks working in office buildings, the stadium and TV station commuting from distant towns or did Mayfield somehow have a very low birthrate with few of its citizens having borne school age children?

Wally made a comment to Beaver in the Fallbrook episode (Beaver was antsy about going to High School) that Mayfield High was fed by 6 Grammar Schools. So that much, we know.

That's right and two grammar schools from Mayfield were represented on Teenage Forum. (Beaver on TV)

Also they had Metzger's Field, Miller's Pond, maybe Friends Lake (since they are taken to Mayfield police station when the boat was stolen. Also they are starting a youth center in Mayfield. (Mistaken Identity). Friends Lake is a puzzle since different episodes give different distances. Ward has quite a drive in Wally's Dreamgirl, Wally the Lifeguard and Fred in Beaver and Violet.

Theres a large office building full of lawyers right in Mayfield. Mayfield was not without its bars, Hank's, the Red Top, Birdcage, Green Door and Monahan's.