Posted by: DIT_grue
« on: January 03, 2016, 12:04:30 AM »4. I believe that there is more money generated from an empire>empire trade, than generated by just trading between your own planets. Also trading can generate more goodwill between you and another empire, making alliances easier.
IIRC the original explanation was that there's half a credit in tax on every unit exported, and half a credit tax on every unit carried. So if one of your lines picks up goods at another empire's colony (it doesn't matter where they ship to), you get half the tax you would if they did so from one of your planets. And if a foreign ship carries goods from your empire, you still only get half the taxes (but the opposite half, as though that mattered ). The reason that it's usually worthwhile is that inter-empire trade opens up more sources of supply and demand, so cargos get moved instead of sitting at the colony where they're produced until they rot to pieces.