I felt that Case West was somewhat justified for having 800 MS points because:
1) It's a sequel. Therefore it is relevant to all future DR games. Compared to CZ (a Demo) where I'm forever stuck at LVL 5 and lack strength, speed, etc.
2) Case West provided for the story. CZ was just a demo and the lac of connection to the main story was a reflection. Sure Chuck was in a zombie outbreak, but that was as easily told in the beginning of DR2.
Overall, CW feels more relevant and something I'm more likely to play over and over again. Since DR2 came out, I've had no desire to go back and play CZ. When I'm level 50 in DR2 and CW, being forced back to lvl 5 isn't appealing.
However, CZ definitely had its moments and as a demo for DR2, it did its job splendidly.