Probably they decided to get their hands on those coins before somebody else does, knowing that sooner or later the whole thing will turn just like btc-e , so why not grab it and act like is an act of justice against
Highly ironic, especially if you check the older threads two years ago when their supporters were shouting btc-e/wex can't be shut down, this is Russia, etc etc.
Probably a combination of everything and something on top of that pile, maybe they are even outside of the reach of the FSB, operating from god knows where and paying that protection fee to somebody else. Or, maybe it's the FSB running it and they disposed of wex? No amount of tinfoil is enough for what's happening there.
Either way, shady as fword, and will probably have a just as shady end.