@micah: also in Man of Steel mini in '86.....or theirabouts...maybe it was Action Comics....
@G-Man: this is the main reason I enjoyed the Mark Shaw Manhunter series way back when...he took on other heroes villains......usually with prep and by surprise when they were "weakest", but still.....
I think Tony gave a well thought out explanation here. One thing I would add is that one of the big things that distinguishes heroes from villains is character flaws, so a lot of times there is an ego involved that consciously or sub-consciously seems to make the villain seek out situations where they must face off against their "arch-nemesis". I think that could be a reason why you see a lot of your low-level bank robbing types like Shocker, Rhino, and Captain Boomerang move around the Marvel U more than people like Green Goblin or Magneto.
Also, great example of an equal opportunity villain who has fought just about everybody, Count Nefaria.
I think when it comes to DC in particular, all of those characters in isolation from each other so the villains are solely developed for that hero; Batman and Superman villains ever crossed over nor did they crossed over until much later. A shared universe didn't exist there. Marvel was more a shared universe but even characters didn't face off from each other. Green Goblin ever faced The Fantastic Four.
what the heck is this question hello this happens all the time. etc
1. daredevil vs electro,kingpin,tombstone, enforcers and many others( all spider-man foes)
2. dr doom vs the marvel universe
3. brainiac,doomsday and lex luther( superman villians) vs justice league