Gray area indeed! Artist alley would be less populated if people would not have the "luxury" of seeing an artist that puts their own spin on already existing characters. Some of us starting do it for love of the industry but also to get noticed in those conventions. I'm not going against this statement at all, I agree with the fact that a company has the right to protect their interest, interest backed by reputation, but personally I like to enter Artist alley and seeing people who take for example a character like Spiderman or Joker and ad their own style and flavor. Yes it's not their character, they don't have rights to it, but would you give a second look at them if they didn't have something you could recognize quickly and relate to? Is that not the reason why we go to comic book conventions or is that in fact what it evolved into? The fact is proven by those who pay their light bill and every other expense with the income generated by commissions. So how do we take this issue forward? The other thing that concerns me is that Marvel and DC prints and sells a series of books that illustrates how to draw their characters encouraging upcoming artist to enter the world of their favorite illustrated comics.

I have 2 quotes to share from the "You can draw Marvel Characters" book by Dan Jurgens. In the introduction, last sentence: "You might just become the next guy to draw Spider-Man clinging to the top of the Empire State Building!" (Dan Jurgens.)

Second one found in page 93 under Resources (Comics): "You will probably find that there are artists that you really like. Now that you have studied the techniques of drawing, you will have a better understanding of how your favorite artists achieve their effects and will be able to copy some of them your self." (Dan Jurgens)

So the desire to go and create because you love the world is also backed up by excerpts building confidence and fueled by artists, like those in conventions, who are extremely talented and keep the legacy of our favorite heroes alive while trying to pay their bills in this and any other economy.
It may sound contradicting, I know, but how do we present how we can not only create original stuff but are able to modify existing material to create an individual artistic entity?