On the other hand, I swap wheels frequently and am too lazy to bother with swapping cassettes & chains and does not matter to me. Each wheel has it's own cassette.

You will need to adjust the rear derailleur a little bit when swapping wheels because the cassette position will not be exactly the same from 1 wheel to another. At least the barrel adjuster for "cable tension", and possibly the limit screws if the wheels are really different.

www.parktool.com/repair has good info.