Whilst raiding non active planets today I have noticed that I am receiving a 50% penalty on raided resources, however I am currently not actually due penalties. Have re-spyed planets after attacks and sure enough 50% of resources are left on the planet. The planets raided have not been without defences and so attacks are costly in terms of vespene usage, therefore attacks must be weighted in terms of actual gain - a 50% penalty applied without notice drastically alters what actual gain a player receives.
at present I am at approx 7% of looting before penalties
What is going on ??