Well, the fact is - they do. Look at it from a literary perspective. Bradford Wright and several other scholars have observed that the archetypal comic book hero resembles the heroes of Greek myth and tragedy: Oedipus was marked by the Fates and Peter Parker got stuck in a pretty damn well fateful situation that changes from incarnation to incarnation, but the end result is the same. Greek heroes and Karmic pincushions are exactly like superheroes in that, to quote the delicious cornball that is Loki, they're "burdened with glorious purpose".Brawndo said:
We generally tend to have a hard time exploring the finer aspects of human nature through art by sticking to purely mundane settings. Even Goncharov's "Oblomov" deals with a fabulously idle Russian nobleman who has more than enough dosh to while his days away in his favourite couch. In an effort to explore the theme of laziness or procrastination, the author puts together a character who has the unusual means to be just that epically lazy. So lazy, in fact, that it kills him in the end.
When's the last time you had to run around extinguishing metaphorical forest fires left and right? I sure haven't, with the most serious stuff I've had to handle in thirty years of existence being job interviews and my own tendency to put things off to tomorrow. You sure couldn't use my life's story as a model of what the noblest of Humanity would do when put under duress. A few thousand years ago, duress was the Gods choosing to lay a Karmic whammy down on you for the lulz. Today, it's the Chitauri invading New York or Bane locking Gotham City down.
As this is what superheroes have been created for. It's in our nature to keep questioning what we'd do in extraordinary situations, or what we'd want to do if we could do more than what we can. We've all idly fantasized on what our life would be like if we had a couple million dollars burning a hole in our pockets, right? Considering, going from that to wanting to figure out what happens when you can design synthetic webbing that's resistant enough to hold your weight and when you have a spider's proportionate acrobatic skills doesn't seem so strange.
I'll admit, however, that there's some cases where a character veers away from honest experimentation and nosedives into Gary Stu-ism. Any fabulously wealthy type runs the risk of falling into that pit, as does anyone with regenerative abilities or general immortality. The thing is that thankfully, most comic book writers seem to focus on the human element - as opposed to what I've seen some other writers do.
You want an example of someone who handles this extremely poorly? Try Anne Rice's later Vampire Chronicles. Louis and Lestat start out being complex and engaging enough, but by the time we reach "Blood and Gold"; one's been reduced to tearful soliloquies and the other's been inflated to Insufferable Godmoded Fanfic Character. Anne Rice's blond baby can do absolutely no wrong, so he gets all the toys, all the abilities, all of the money, all of the attention. Christ, he's even been able to kiss the actual Shroud of Turin in the previous books, or to take a daytime stroll through the Gobi desert!
So much for being a vampire, right?
The thing is, Rice forgot her initial goals. Her vampires, like most superheroes, started out as a means to explore themes of loneliness or isolation amongst marginals. That's a fairly common trope for vampires. Then, just around the same time us geeky or nerdy types started to gain representation - Lestat shifted gears. His insolence wasn't the product of brazen confidence in the face of adversity anymore - it was basic verbal masturbation and blatant wish fulfillment.
Then, as we all know, Stan Rice kicked the bucket, she got massively depressed, found Jeebus and rejected her previous works. Yawn.
So comic book characters are prone to the same excesses, depending on who writes them. Some people will put together wonderfully deep storylines for Batman et al., while others basically go "Oh hey, he's a billionaire! COOL TOYS AHOY, #SWAG." It's a pretty serious case of missing the point, but what can you do?
Superheroes are different things for different people.
