[Jason Abbadon]

Exactly.
While the odds are that asked people wont have guns, they can do stuff like destroy entire towns (as Count Nefaria did while fighting the Avengers)- or kill school bus full of kids (as the Wrecking Crew did) or rape a woman knowing that the cops and their guns are no threat (as Absorbing Man did) or destroy much of Las Vegas as the Hulk did and years later Gravity and Hardball did in Fear Irself..
The general populace has no way of knowing masked heroes from masked villians- they cant keep score of the hundreds of costumed people out there. Even the "heroes" are unrstrained and destroy everything- people's entire lives, jobs and homes gone becaise Gravity was pissed at Hardball for insulting him.

That's life without the SHRA under Steve Rogers.

Hell, it's amazing that the poulace of the MU does not just shoot any costumed people on sight from rooftops!