Okay, that it explains it. I have never seen anything anywhere that stated this. Ah, the joy of playing an alpha.
The reward is shown when you hover over the mission description, it's always 1000 gold, 20 (?) wine and 10 kingdom points (Is it called that? The crossed swords. I'm playing in german so it might have another name in the english version).
Also a notification pops up as soon as your soldiers have returned.
Okay, thanks. I have never hovered over it before. It is so dark, though, that I would never know that is wine. All that I see is a little bit of green and the number 20. They need to make those icons brighter or use a lighter background so that they stand out more.