why would this door be here?
 

i was glitching around ( again ) in tortuga and i saw this door to kings arm why would they put it there?

It's just part of the design of the building. If you'll notice, the SVS islands have the exact same tavern, and they have a back door as well.

Notice that building. It's also on Cuba, and that door can be accessed as a back entrance.

It's just the model. Because you can't see the back of the building, Disney didn't really need to bother with taking the door away from the model, just because the inside only has a one way door.

That's all it is. What would be interesting is if you could go into the building through there, now that'd be a big mistake on their end.(since there's only one door on the inside)

I THINK there might have been something like that with a Tavern, though not sure which one it was. You could go through the door, but you couldn't go back - the inside door was there, though.

Maybe my mind's playing tricks on my memory, but for some reason, I feel this was true...

All establishments need an emergency exit and a service access for bringing out the trash and bringing in the rum supplies. It is Cast Members only.

When you enter you pop up in the center of the tavern.

Before the islands were designed, you could enter/exit the back of one of the taverns. Even though that's not the one pictured.

But yes, as the others have mentioned, they use the exact same models for nearly everything. I guess they don't think people will notice. A while back I went on the boss battle and glitched off, ALL of the forts look exactly like Kingshead (except some bugs that you can't see unless glitched), and the town just contains random buildings found throughout the game.

You can get in through there. It just dumps you in the middle of the room.

It kinda actually puts you near where the La Bodeguita backdoor is located, but a little more forward. The Tavern is also on the Starting Tutorial island, Rambleshack.