Yes but that was when the Avengers, and all Marvel characters were not big names!
Spiderman, Hulk, Thor & Iron Man etc were all still fledgling characters, so who was to say that Hawkeye, Scarlet Witch or Quicksilver were not the next big thing?
Captain America was the only character in the Marvel universe at the time, who was a legitimate "marquee" name!

Now days, having a superteam like The Avengers or JLA without the top guns is almost unheard of!
The last time anyone tried something like this, and I think is more comparable, is Justice League Detroit!