
Indeed.
I'd have been more impressed had you noted that Sergei Udaltsov, whose photo you posted, very often wears black as part of his trademark image as a political outsider. You knew that, right?
Of course the various parties are going to display their own flags. Duh. I don't think that any reader would have jumped to the conclusion that political parties would dump their logos and conform to white.
I don't expect visitors to Russia to have a complex grasp on every nuance so what I communicated was that for a FOREIGNER to wear white or carry a flag on this day in Moscow wasn't a good idea.
But just so we can be on the same page, let's go over the colour scheme of these protests:
1- Domestic accredited journalists must wear a yellow/orange top or vest with the Cyrillic lettering for "press" somewhere visible.
2- Foreign credentialed journalists must wear a blue top or vest with English lettering for "press" somewhere visible.

Bloggers/internet sites don't have to conform but many do as in some cases it affords some amount of protection against detention. Then again in some cases it invites detention.

In the photos above and below: Rally organizers Alyona Popova (2nd from left) and Mariya Perfileva (far right) wear white and carry white flowers. These photos are from earlier today.

From the very start of these protests in December, WHITE has been the identifying colour in these protests. It stands for clean (white symbolizing pure) elections and a fresh start. The WHITE ribbons that Mr. Putin joked were condoms was a way to identify oneself as a part of the movement.

WHITE has been the "logo" colour from the start of this movement.

Yes, indeed.