Sadly, I don't agree with what was done in regards to the Olympics. I think that what should happen when any country has a big overpopulation of stray/feral animals is to attempt very vigilantly to adopt them out to caring citizens, and also work to spay and neuter animals so these types of things don't happen in the first place. But, when there is an overpopulation of unwanted animals, sometimes euthanizing animals is the only way that the problem can be dealt with.
To those that are so angry about the Russian officials killing stray dogs in Sochi, let me ask you: where do you live? While I can't speak for other countries, here in America, we killed huge numbers of dogs and other pets yearly in pounds. So its easy to be outraged, but we shouldn't be hypocritical.
Yes, Sochi officials should kill all stray dogs in preparation for the Olympics, because they might hurt people. If they will make the guests uncomfortable, there is nothing wrong with not wanting stray animals around. There are reports that the animals are even in finished hotel rooms. There is no reason to needing to have these dogs running around.
The stray dogs roaming around Sochi shouldn't be killed in preparation for the Olympics. However, officials shouldn't kill these stray dogs. Rather they should be rounded up and moved elsewhere. They could be re-homed, and some dogs might need to be euthanized should they pose a threat to the public.
To deal with the Sochi dogs, we should move them to a restricted dog area. Let me be clear, dogs are not humans. It is okay to contain dogs, and it has no bearing with the containment that happens with certain ethnic cleansing purposes. Keep the dogs away, but don't kill them.