[RamsHead]

The way I understand it, it is not a bug. Although it is not explained very well, the "bonus" is that Abysia is not affected by the initial effects of a growth/death scale. In other words, Abysia will not suffer -6% in their income from a 3 death scale, but the population in that province will still die. The fewer people in a province, the less money you will get. It is only the initial income and supply effects that Abysia is immune to, not the longterm consequences. Since, as Abysia, it is likely you will go with a growth scale, this "bonus" is really a penalty.