On Published Settings

I abhor published settings. Or at least, that's how I phrased it when the subject came up in conversation. This, of course, was bound to provoke a bit of controversy.

"I can't understand that mindset. Like. Have you READ Deadlands?"

Alright. 'Abhor' may be too strong of a word. I can actually enjoy published settings for their fluff. A lot of settings I quite enjoy, especially when they come from an actual work of fiction, rather a campaign book. If we want to make my initial statement more accurate, I abhor running published settings. There's a handful of reasons for this, some more practical than others.

1. I'm huge on communal setting creation. I want to create something in the broad strokes and then fill in the details through play.  This was how I grew up playing these games in my early teens. We sketched out a map or a came up with a setting and then it just got filled as we played with it. New locations and things were introduced as a natural outgrowth of play, rather than as a concerted world-developing effort or referenced from a gazetteer. As a natural consequence, these worlds were always ours, unique to the people who shaped them and often colored by our own mythologies. Funny enough, this style of world-building seems to be popular both with the OSR crowd and the Burning Wheel/Apocalypse World/Story-Game crowd.
2. I'm a history nerd. I spend a lot of time memorizing the details of various cultures and eras in the real-world's history. As a result, I can pretty handily fill in the gaps of whatever broad-stroke setting I was running with bits from history without missing a beat. Even something as small as just nailing the material culture of a society or setting is something that I really enjoy. It helps flavor the thing and makes it stand out. To bring that same level of loving detail and attention to a published setting, I'm effectively going to have to study a whole new culture and history while trying to parse how much it leans on this or that historical period/culture and where it deviates and the specific bits that make it worthwhile on its own. Even settings I legitimately enjoy and am familiar with from fiction (Middle Earth, Star Trek, Star Wars, Westeros) would require me to go back and study them for a while before I'd be comfortable trying to represent them. This could simply be a hangup based on unchecked perfectionism, on my part, but I'd rather spend my time studying earth history than Westerosi. The former is far more interesting than most people would believe.
3. I enjoy GMing as an act of creation. Writing stuff and creating fluff is half my fun of doing it. The more details that are published for a setting, the less room I have to carve my own niches into it. This actually creates a weird double-edged sword for me. A setting too tightly constrained will lose my interest because I want to create for it, but a setting too loose will make me question why I'm bothering with a published setting in the first place. Does a sweet spot between the two exist? I'm not sure.
4. I don't want my players to know more about a setting than I do. There are a handful of reasons for this by itself. The most immediate is that I don't want to introduce my players to the governor of Waterdeep only for someone to inform me that Waterdeep is actually governed by a council of retired adventurer-nobles or some nonsense. The more popular a setting is, and the more stuff has been produced for it, the more likely my players are to have read it and the less likely I am. I simply don't have the patience to go through three hundred forgotten realms novels. Before one cries "get players that won't be assholes," this isn't because I'm afraid my narrative authority would be challenged (I have good players, and it's easy enough to say "not in this setting.") but because...
5. I mentioned before that I'm a big history nerd. My favorite settings are the "viking age" — northern Europe around 900AD — and various places/times in ancient Greece, classical and mythological, alike. Being a visual creature, I am naturally a big fan of movies set in these periods as well. Unfortunately, movies are absolutely terrible at actually representing history in any appreciable way. I've never seen a sword and sandals movie that bore anything more than a passing resemblance to ancient Greece. Viking movies get a little better, but even the Vikings show on the HISTORY channel is nothing close to the actual period. To enjoy any of these, I have to actively turn my history brain off and pretend that what I'm watching is actually a fantasy universe set in the flavor of the thing being represented, with all likenesses to places and characters a complete coincidence. Otherwise I'm like to point out that "We shall not interfere with the lives of mortals," is not only a stupid plot (Lookin at you, Immortals) but that Greek mythology is literally nothing but the Gods interfering with mortals. I don't want my players knowing more than I do because the whole point of playing that setting is to give them the experience of that setting. Every time I get it wrong or diverge significantly from canon, it's detracting from the reason I was using it in the first place.
6. It removes some of the mystery. I don't want my players having a Word of God absolute knowledge of the history of the setting. I want them to know basically what their characters know. It makes the history that much more interesting when we can be uncertain of it and surprised by it. Likewise, you lose all dramatic impact of any kind of Lovecraftian plot when the players read on page 47 that the council that governs Kingdom Y is actually a dark cabal trying to summon Shub Nuggath, the Toothstorm. 
7. Finally, settings are meant to be destroyed. I tend to make my players protagonists in the literary sense of the word. Within a few months of play, they're going to have shaken up the setting enough one way or another that they've overturned the most of the original status quo's anyway. Why put all the work into memorizing an establish setting and getting all of someone else's details right when there's a goodly chance the players will have burnt it down within the first campaign arc or two anyway?

That's enough rambling for one afternoon. I don't have any problems with other people running published settings, nor would I particularly mind being a player in one. As a GM, though, the effort/reward ratio is way off and in some ways it actually runs contrary to what I actually enjoy about GMing.

Am I crazy? How do you feel about published settings?