Really depends on the country. And in a country could friend on the city. For example, in the Soviet Union, Moscow was off limits to the people who did not have a permanent place to live (as registered in the internal passport). They were forced out but not necessarily imprisoned, just moved to "the 101st kilometer" (outside the 100 kilometer zone, that is). I think Leningrad was like that too. Even in the USSR it was uneven: Russian and I think Ukraine were like that, the Baltic republics were not, not sure about Central Asia.

These are all historical anecdotes, nothing more. No claim about it being or not being intrinsic to the socialist society etc.