I know Cunningham and Weber are last names that people in reality have; but what about Piccolo, Fonzarelli, and Malph? One example of someone with the last name Weber in reality is bikini model Amy Weber. Anson would not look as good in a bikini as she does. Delvechio is another one, and so is Arcola as far as the main characters.

While Piccolo DOES exist as an Italian surname, as far as I can tell, there's no one outside the HD universe with the actual surnames of Fonzarelli or Malph.

they must have been invented or gussied p names from the writers' real lives

I read that Garry Marshall came up with Pinky's last name Tuscadero after he saw a sign with the town of Atascadero. He dropped the first A and changed the second A to a U.

I know Cunningham and Weber are last names that people in reality have; but what about Piccolo, Fonzarelli, and Malph? One example of someone with the last name Weber in reality is bikini model Amy Weber. Anson would not look as good in a bikini as she does. Delvechio is another one, and so is Arcola as far as the main characters.
And Arcola too.

There is a Fonzerelli auto repair shop in New Jersey. Not sure if they named it after the Fonz (who also ran an auto repair shop).
https://www.fonzarellis.com/

All those Italian sounding names in Milwaukee, but no Polish sounding names makes no sense anyway.

Piccolo

My former boss.