Russians have always been heavy drinkers of vodka and they always will be. Medvedev is just trying to look nice by pretending to care for the people. In reality, it's probably a plot to get more money from the huge vodka market.
Medvedev has nothing to fear from bad publicity. The worst that can happen is he's going to be replaced by Putin. Medvedev is nothing more than Putin's willing puppet anyway. There is no political opposition to the current regime. They've either been killed or imprisoned by now. Most of the media is government controlled.
Thanks to vodka, the Russian people can survive yet another century of repression. They've done it for centuries...
And another reason the Russian population is dropping is because of the very high child mortality rate and low birthrate. Kids are dropping like flies due to diseases that have long been cured, that's how shitty the current health care system is in Russia. Birthrates are so low that they called last year, the Year of the Family, and the government organized all sorts of tax benefits just to get people to make more babies.
Oh and a huge number of people still live in shitty villages without electricity.