Serbia is not a EU country.The poorest EU country is Bulgaria ( I should know, I'm from there).
I have been to Brazil and the situation is very different there. You are correct that the GDP is comparable, but the gap between the rich and the poor there is far worse, though I don't have the stats to back up my claim. Just an observation.
That being said I'm sure that the short term profits they make from cutting the rainforest will definitely only help widen the gap between the rich and the poor there. I agree with you that they have other options to better their situation in a more sustainable way.