Hey Madmole. I was surprised to hear that you only now discovered that there are traders in every boime. But yeah, it's like that in Navezgane. Trader Jenny is the hardest to find

. Mainly because unlike most traders that are on main roads. Jenny is on a side roads. Side roads are very hard to see in the wasteland biome.
In Random Gen (RG) I can find a trader in in every biome. Which gets a little weird when I find more than one trader with the same name. Because in RG, I find several biomes of the same type and each with it's own trader.
For example: I will have a several pine forest boimes and find (a) Trader Joel in each of them.
Having them always by the roads is both practical and helps others to find them and l love that.