Could it also be that amongst the 3 Baltic nations, with relatively small populations (total is under 7 million) compared to countries like Germany or Poland, and an economy that has been hit hard by the recession, that passengers simply aren't willing to spend enough on flying to keep 3 separate Baltic airlines going ?
SAS is going through tough times while being the principal carrier for a population of about 20 million (yes, I know about Norwegian) along with the benefits of membership of a major alliance. What chance of Lithuania, Latvia and Estonia each being able to have an independent airline of their own ?