Various boards have discussed Jonah's dislike of Spider-Man with different degrees of seriousness.
The Sam Raimi movies play it up as Jonah isn't sure *what* to make of Spider-Man. There's a dislike of masked vigilantes, an uncertainty of why Spider-Man does what he does, and speculation that Spider-Man just can't be *that* noble. Anything like "Spider-Man heroics attract those super-powered nutcases!" seems to saved for Christopher Nolan's Batman movies.