Simply put if that gas goes over land that gives for example Poland bargaining power over a strategic German/Russian investment. I am not private to the particalurities of this venture but it could be that the associated risks are too costly.

Probably, the reason is in the first place an economic one, rather than a political one. A particularity of the Sovet era that is still in effect (be it not for long anymore) are the artificially low energy prices (also for gas) throughout the former USSR countries (including Eastern European countries like the Baltic states, ...). In 2004, domestic gas prices (to industrial users) were on average only $30 per thousand cubic metres, while world market prices on average were around $140 (!) per thousand cubic metres of gas.

Today, Russia is still in a process of economic transition from a centrally planned to a market driven economy. Therefore, it is - as a part of this transition - trying to gradually increase these low energy prices to a world market price level. Neighbouring ex-USSR countries (such as Belarus and Ukrain) are indeed affected by this, but so are the end consumers in Russia (!).

This gap between domestic and world market prices makes that 70% of Gasprom's revenues are generated by only 30% of its sold gas volumes (being Gazprom's exports). Moreover, transiting gas through other countries comes at a cost: transport fees have to be paid per km and cubic metre of gas that is transported. This results in a higher gas price down the pipe (i.e. Western Europe). From this picture it is clear why the Russians are so eager to sell their gas directly on the Western European market.

Of course, there is certainly also a political aspect to the construction of a direct link between Russia and Western Europe: (i) A policy of cutting the subsidizing of gas supplies creates resistance in (former USSR) gas transit countries. However, in my view, this resistance is not the main reason for the Russians to construct the NEGP. As I already argued, the main reason is an economic one. Everything should be seen in the light of one strategy: "selling Russian gas directly on the European market". The NEGP is only one aspect (be it an important one) in this strategy. In parallel, the construction of several gas storage sites (underground) throughout Western Europe is a key building block in the Gazprom strategy. Underground gas storage acts as a buffer (gas reserves for winter) in case things go wrong logistically (in the transmission network or due to political instability); (ii) That the Baltic states express their concern on the construction of the NEGP, is understandable, but nevertheless driven by an ungrounded fear. Since their negative Soviet experience, the Baltics perceive the Russian bear as a threat, even after EU membership. All actions they take vis-à-vis Russia and the Russians are driven by self-protection (cfr. the treatment of Russian minorities in the Baltics). I guess it will just need some time and common sense to overcome this fear and deal with Russia as any other political and economic partner in the international arena.

Perhaps because they have problems with the Baltic states and their treatement of Russians.
Russia is also a bit nervous because NATO is creeping up towards them. Typical Russian reaction of 'fear'. Seems it has found a European ally in Germany, perhaps to strengthen its position towards the EU and the Osterweiterung? One thing bounds them: Kalinningrad or Köningsberg.
Perhaps the main gasline will be -eventually- extendable towards other European regions (Scandinavia & Eastern EU). It seems to be a safer solution and wont suffer any possible criminality problems.
I remember something abt talks between Belgium & Putin on storing Gas and making Antwerp a main Russian Gashub. A Bit like the St Petersburg policy, a shift towards Europe but in a more assymetric manner (perhaps).