Writers always base their villains (and characters as a whole) after something. It speeds up the creation process.
I always liked JMS' totem explanation. It explained Spider-man's villains, but also Captain America (always fighting fascist and anarchist, terrorist type characters), mutants fighting mutants, Hulk fighting other gamma mutates, etc. Although it's just a fancier way of saying what others posted above me.
Rhino: "I'm a rhino, you're a scorpion and he's an octopus, what's a Mysterio?"
That's somewhat enforced by the writers and audience expectations.
Stan Lee originally wanted Green Goblin to be a resurrected supernatural entity, but Ditko nixed the idea because he felt that that would be too out there for the genre he wanted. It's the same reason why they decided to retcon the Tinkerer, who was originally implied to be an alien, to being a normal human being.
Have you ever thought of what Spider-Man would be like if they didn't decide revise their ideas? Most people I read prefer them as they are now. It's why Spider-Man is "street-level" hero. People prefer him to be there.
Anyone else wonder what would happen if he fought his Japanese villains like the Machine BEMs and the Gokibu?
I guess it’s because the villains’ theme, animals, will match with spider-man. Not only that, most of his villains got their powers from an accident which is the same for spider-man as well.
We are all savage animals and beasts, clawing at each other in some hopeless attempt to find purpose and peace. Except Quentin. Quentin is God.
I don't blind date I make the direct market vibrate