Marvel sells what Marvel sells.

When I bought Pegasus Books in 1984, it was primarily a comic book store. And what sold in comics was, to winnow it down to basics, X-Men, X-Men, X-Men (and a little Spider-man.)

I spent much of my paltry initial budget at comic books shows buying up all the back issues of X-Men I could afford. Chris Claremont was still writing the storylines that have become so basic to the Marvel Universe.

As time went on, Marvel diversified--into X-Force, Excalibur, X-Factor....well, you get the picture. Plus a host of individual characters, Wolverine, Kitty Pryde, Cyclops, Storm... (all kinds of characters, as long as they were X-Men.) The occasional Daredevil or Fantastic Four (the latter which always seemed to flop, and still does...)

Even then, I thought it was strange how Marvel all but ignored The Avengers, and the individual Avengers--I mean, I wasn't a huge comic person when I bought the store but I was well aware of the Hulk, Captain America, Iron Man, etc. 

These titles came out but got zero promotion; they got artists and writers who were second-tier or just beginning their careers, and so on. 

When people would say to me, "You must be selling tons of comics. They are so hot," I'd answer, "How many copies of the Incredible Hulk do you suppose I sell? I'll tell you: 3. 

This was true for most of the Avengers. They just didn't sell.

And it made no sense.

So what happened?

What happened was the Marvel in their financial struggles had sold off the rights to the X-Men and Spider-man and Fantastic Four and Daredevil. They got little of the money from the hit movies.

All they had left was the Avengers.

It's interesting to look back at how there was some doubt that the public would go to an "Iron Man" movie. Seems ludicrous now. (I thought at the time that the "experts" were underestimating how much the Marvel Universe had pervaded the public consciousness.) 

So they switched gears and the rest is history. It was such a reversal that for awhile I couldn't sell the X-Men anymore. It was reversed: I was selling dozens of the Hulk and three copies of X-Men.

The point being--whatever anyone turns their full efforts and attention to--that's what sells. It can take some work and it doesn't always succeed, but roughly that's how it happens.

There is only so much prime space and it can be hard to squeeze everything into that prime space, so all of us purveyors of pop culture have to pick what to promote. 

Marvel got incredibly smart about their properties. Sadly, at the same time, they started neglecting the comics side of things. The movies make so much money that comics seem paltry in comparison.

Of course, from a comic shop owner's perspective, comics are the Golden Goose and we retailers are the ones who have fed and protected that goose for decades.