Did not check coordinates, and it is campaign so I can't make plane atm. maybe I can check same map seed in creative.... will try that.
I was going north to 4k to find salt flats in early game, and at some point i turned west, and for 2k there was only trading station behind me.
Map seed "QuestForAchievements"
You can confirm map is good if you can find Pillars biome at -2148,5276
If you get there by going straight north from start to 4k then turning west north-west you will pass last trading station on -1000,6000 then next one on 6k line is on -5000.
I just did a bit of exploring in a random Creative map, and in the course of travelling about 25km, I found 3 to 4 spots where a trade station was missing from the 1km x 1km grid. (Including at the location in the attached save.) So about 1 in 6 absent, at most.
I'm wondering if this is a new feature (or not)? @Greg? I thought maybe that they no longer spawn if the terrain is too rough, but some of the empty spots were flat, clear desert. So maybe it's just random, to keep things interesting.
Correct, a Trading Station might not spawn if the chosen location is deemed unsuitable. At the moment, it doesn't look like we try to find an alternative nearby spawn location but we should probably change that in the future.
Also interestingly, the 1km x 1km grid is more of an approximation than an absolute, so they may sometimes spawn slightly offset from their expected position.