It had happened all 3 times I returned from vacation now. My sims would appear at the door, and suddenly, right in front of my eye, sim is teleported to Buena Vista Resort. Might as well since he is there, he would walk around and hang out at the resort, and when he was chitchatting in hottub, suddenly he appears at the house's door again, fully clothed.

2nd and 3rd time I was not focused on sims. I saw them briefly at the door, then I went ahead to move in all the souvenirs in the house, and suddenly notice the sims riding home from some roads far far away.

This is in Bridgeport btw, and 3 different vacations are from 3 different households to all 3 different destinations. I am not griping about this as my game still runs and not crashed. But ... I hope this is not something leading to a corruption.

Strange. Whenever I've had sims who lived in Bridgeport return from a WA destination, they usually start driving from around the Science Facility area. Then again, I don't have them live in condos. Generally I have them live on a lot near the rest of the high end/mostly celebrity area.

So far, I haven't experienced any corruption (well, not since installing Overwatch back when I did).

I think what you're describing is the normal behaviour. When Sims travel they are being exported from the base game and then imported into the travel adventure game, i.e. basically it's clones of your Sims that are in the vacation worlds. When they return the vacationing clone is exported from World Adventures, imported into the base game and merged with the "real" Sim, which then gets "updated". This is the main cause for all those glitches with disappering Sims on arrival, destroyed inventories and broken family trees.
Now it seems that this exporting routine does not take into account the location you're Sim was at when they started travelling and on returning it puts the Sim first into their home and then teleports it to a location on the borders of the map that appears to be the furthest away from their home.
I have observed this in every neighbourhood so far and this teleporting is most noticeable when you start a vacation from some community lot, because when you return the camera will focus on that lot first for a moment and then zoom out as far as possible and centre on your homelot.

While your theory makes sense, but all the time I started vacations right at home. But regardless of where in house I started, my sims would always return home to the front door (like sims just moved in). My case was not the camera location, but I did verify that I saw the sims standing at front door, and being teleported away to some locations that I have never been to. Not even once since I got LN.

I may have been not clear enough, but as I said, this seems normal to me. When you start a vacation from a community lot, after you return, even though the community lot was your starting point, your Sims will appear for a short moment in front of their house and then be teleported to the remotest location from your home lot. When you start from your home lot, upon returning your Sims will materialise shortly in front or inside your home (I guess that's the refernce point for export/import) and then teleported away to the remotest location from your home lot.
My Bridgeport family lived in a highrise apartment near the movie lot, their re-entry point after vacations was Buena Vista, too.
My Riverview family lived south of the River, their re-entry point was the Newbie house.
I have one family in Barnacle Bay that lives on that lot on the little island that is connected to the rest by a bridge. Their re-entry point is, I think, one of the park lots near the defunct graveyard.
My other family lives exactly there. Their re-entry point is, funnily enough, the residential lot on that little island.
And I can always see them for a few seconds within their houses and then they are teleported to the re-entry point.
You will also notice that when your Sims travel they will actually not always leave their house. If they are, let's say on the 3rd floor, the loading screen will start before they have even made for the door. But nevertheless, when they return, they will be teleported to the remote site and take a cab or whatever home. And if you look at your home lot, more often than not the taxi that was supposed to take them to their vacation will still be there, too.