Actually you are both correct. The time period in question was of collectivization. Farms, peasants, were brought under government control. Many due to the abject poverty of the situation moved to the cities.
Poverty and privation drove people from the countryside, while Soviet official industrialization campaigns encouraged (and sometimes forced) their movement to cities.http://kommunalka.colgate.edu/cfm/essays.cfm?ClipID=376&TourID=900
In my reply, I was speaking more about the period of from 1950 to the 1990s. During other periods, other circumstances may have prevailed. And when saying "cities," I wasn't referring to just bigger towns and such - but was thinking of metropolitan conurbations like Leningrad and Moscow.
Regards,