I think we develop fandom at an early age. I think fandom is a byproduct of our ability to conjure up make-believe worlds when we're young. Fandom is what we do after the book is read or the movie ends.
For me, fandom was most evident in the Back to the Future franchise. I built the time-traveling DeLorean out of Legos, and made mini-figs of Doc and Marty, (and even Jennifer, Biff, and George McFly), and they'd go on time traveling adventures that went far beyond the scope of the movies. I suspect others took their love of these movies, their fandom, and when they grew up they got jobs at places like Lego. This is probably why you can buy your own Back to the Future DeLorean, which, I'll admit, looks much better than the one I had made as a kid. Judging by Lego's track record in resent years, it would appear that there are many fans of many different nerd properties, currently on the Lego payroll. For a long time I was annoyed that my Doc Brown's, Jedi's, and Ninja's were all home made, mostly from old spaceman mini-figs, while the younger generations got their own, made-by-Lego sets.
Lego is but one example of what happens when fans finally get what they want. Those of us who watched after school cartoons and had an original Nintendo Entertainment System, will have fond and frustrating memories of the Duck Tales video game. Less than a week ago the 'remastered' version of the game came out on all platforms. I have not played it yet, but I'm anticipating there to be several moments of nostalgia. I'm also sure there will be a lot of new things added thanks to the substantial advances in technology since the game's initial release in 1989.
And alas, another thing that I can be sure of, without even scouring a search on the subject, will be the amount of droning nay-sayers who will do nothing but complain about the inconsistencies with not only the original game, but with 'non cannon' elements that were not in the show or even the comic books written by the creator of the Uncle Scrooge character, Carl Barks.
When it comes to fandom of any form, the Internet turns into a raving incarnation of Comic Book Guy from the Simpsons, condescending over new ideas as if, they alone, hold the truth and laws to what they consider to be their claimed lands of the nerd kingdom. There is no room for discussion when you come up against these Nazi's. They will tell you that you're wrong from deviating from the creators original content and treat you as if you are stupid for thinking any way but their own. These basement dwellers typically lurk in places like Reddit and wait for voices of descent to arise so they can climb up on their armored mechanical demon-horse, after putting on their quad-XL gold-farmed armor, brandish this magical keyboard of doom and lay waste to the interloper that goes against the status quo. They feel power at doing this. Hell, they probably get off to it when they're all out of porn to download. And they do this because their lives are so tiny and insignificant outside of their Dr. Who DVDs, their extensive collection of comic books, their Harry Potter fan fiction, and the fact that they know how to speak Klingon, that without this, they'd have nothing worth living for.
Comic Book Guy on the Simpsons is ridiculously funny. His humor can be felt on many levels. On the surface he is funny for being a nerd. Nerds are funny. Sorry nerds. You may have one the culture war from the oppressive 80's, but you'll still be the butt of many jokes. Comic Book Guy is also funny because many of us see ourselves in that condescending fat man. Again, fandom is learned at an early age. And when we're young, most of our make-believe occurs in a lonely place, typically in our own minds. There are no dissenting voices telling us we're wrong. We make these rules, we shape them in our own image. We are the dreamers of dreams.
And when others try to change the rules, we, like Comic Book Guy take offense. We can either engage in thoughtful discussion, or, since the Comic Book Guys of the world are loathsome individuals with little going for them and no chance of ever getting laid, they will resort to regressing to their land of make-believe and reign on high belittling any opposing thought.
I have no time for these sorts of people and I secretly hope that the Darwinian notion of Survival of the Fittest, or a zombie apocalypse will ride the world of their ilk. It's no wonder that these parasites fester on the boarder of another 'dom' in the cultural multi-verse: trolldom.