The real reason Spider-man wasn't in the Avengers

He would have solo'ed Loki.

LOL

I thought because nobody would have cared about him on the team.

I was under the impression it was because somebody aside from Marvel owned the rights-

... And by that I mean he totally would have solo'd Loki. Go Spider-Man.

Sony.

I'd say Sam Rami, but what the hell, it's Sony's fault.