Fred:
While the double wedding ring symbol on top of the cars is a delightful and sweet symbol for happy & long life together..... the Russian people seem to have a rather dark side to their humor.
Call it cynical if you will.
They look at the 2 wedding rings and make the joke that the marriage is starting off with a score of zero to zero.
Given that the divorce rate seems to be rather high here (example:our guide tonight has been divorced twice!), the cynical approach may not be so off base. Of course, it just *might* be possible that the cultural history of life in Russia may play a part in the dark humor. Just maybe.....

Doug