Russians like their pointe shoes to be well broken in. So they first wear a new shoe pair for many days to rehearsals until they are sufficiently comfortable to be worn on stage. By that time the shoe pair gets understandably dirty. Couple this with the fact that Russians indeed have taken en masse to wearing Gaynor Mindens, which, as mentioned above, last longer, and get worn longer thus getting even dirtier. But I agree that, whatever the explanation, it is still unsightly to look at their coal-black soles and tips. Isn't there any powder or paint to mask the dirt?
On Grigorovich's version of Swan Lake, I must admit I am a bit puzzled by all the negativity here. I personally think this is the best version of this ballet, with all the fairy tale silliness taken out, and the plot indeed made more "streamlined", common sense and coherent. It is a clear parable about the fundamental unity of good and evil, founded on their juxtaposition, as one would not exist without the other, and the inevitable tragedy and destruction of the youthful longing for beauty and purity that is unattainable among the dark realities human existence.
Most importantly, I think the removal of the archaic, time consuming, incomprehensible and dull mime, while preserving the beautiful "dancing" bits of Ivanov/Petipa and inserting new dancing sequences throughout, was a definite win for Grigorovich. In ballet I want to see artistry and action expressed through dancing first and foremost, and I believe that beautiful jumps and turns are a lot more expressive, inspiring and exhilarating than then endless walking about and gesticulation.
And I am by no means an indiscriminate Grigorovich fan. While I see him as one of the more important choreographers of the 20th century, in addition to successes (as I see his versions of Swan Lake or Spartacus), he has had his share of works that were either mediocre or even abject failures, such as his Romeo & Juliet.