Though Spider-Man exists in the same universe as the Avengers, we may never see him in a movie with Iron Man, Groot, or any of the other characters that Marvel has been entertaining the world with for 7 years now. Why? Because so long as Sony owns the movie rights, Marvel Studios, who owns the rights to all of those other characters, can't touch him.
Instead, Sony seems determined to ruin the franchise with shoddy sequels and spin-offs, the latest of which is a rumored film focusing on the previously non-existent espionage exploits of dear old Aunt May.
The continued destruction of the Spider-Man franchise is one of the greatest first-world problems facing pop culture today. Giving the character back to its proper owners would inevitably be a boon to the American economy.