Since the 70s, when I started playing, I have always run my campaigns in worlds of my own devising. As a DM, half the fun of things for me is creating the worlds.
Another for homebrew. All of my games have always been in the Shadowend. I like Greyhawk and the Forgotten Realms and Al Qadim and Kara Tur and so on and so forth, but I only actually game in the Shadowend.
Homebrewed version of Greyhawk. GH is my default because of its low level of detail. One can plug in nearly everything not too outlandish. On the other hand I focuis more on adventure/story than on background, so I could easily exchange Greyhawk for some other world.
Runner-up in this list would be Ptolus, in which I run one camapign and co-DM a second one.
Warhammer's Old World has become my go to setting since 2007, though I'd rather run a Rules Cyclopedia Mystara game. Of those listed in the poll, Dark Sun is the only one I'd want to return to, and that's depending on what edition.
Why is that a surprise? Even RPGs explicitly tied to specific settings have people adapting them to others. It's hardly a surprise that less specific games show people doing their own settings with them. And I suspect even the people using official settings often play in less-developed areas - that's certainly the case in my Traveller campaign, set in Daibei, which has seriously limited canon material.
I've never run a game in an official setting. Even if I did, I'd be hard-pressed to call it a "home" over the one I put work into establishing.
I've played in published settings and I use them occasionally for inspiration and mechanics, but if you're only asking about people who both play D&D in one setting and use one that's published, that's a niche within a niche.
Note that the poll choices are not D&D-specific. He has Shadowrun, WoD, and other non-D&D stuff in there.
When I run D&D, I tend to hombrew the world. When I run other games (I have a long-running campaign in Deadlands, and I'm starting a once-a-month game of Shadowrun) I tend to use the game-specific setting.