The 200 is generally a very nose-heavy aircraft to begin with. Just look at them--everything in front of the wing and not much behind, except baggage. Therefore, if "up front" is full, and not much in the aft, it easily gets out.
They actually have a fairly generous C.G. range, but you do have to keep the folks a bit more aft as a rule. Problems do arise on short business shuttle operations where everybody shows up with a briefcase and an overcoat and nothing else, since there ends up being nothing to hold down the rear. The 700 series has a fair bit more behind the wing, and as a result the problem isn't really there to start, and it has both forward and aft cargo to help move the CG around as needed.