Countries giving up?

Is it possible that some neutral countries give up and don't defend themselves if I attack with a much bigger army?
The reason that I'm asking this is that I just attacked Seoul which had 8 militia in defense. I had a much bigger army with a lot of tanks. When I conquered the city, I all of a sudden had 8 militia in my army that wasn't there before.

No, this is normal when capturing any city: you get the same number of militia as you can make reinforcements in that city, free of charge (except upkeep)

Additionally, some cities have infantry - if you conquer these you will not get infantry you only receive militia.

Ok thanks guys