It’s not a grain excess, it’s a lack of oil exports. You don’t sell off your food unless you are absolutely desperate. With the Russian economy based on 75 dollar a barrel oil, they are screwed.
This is a prelude to war.
As always, the Russians have a transportation problem. They don’t have a grain shortage. They are not going to war with anybody, they don’t have the military to handle a major ground war and they have a whole bunch of Romanians, Poles and Ukrainians who’d love to kill some Russians. There is absolutely no reason that Russia should not be as wealthy as Canada or Finland, the problem is cultural.