Probably because they don't think the NHLPA's offer will fix the problems. In the last lockout, they agreed to some things that they thought may have worked, but as we have seen, those changes didn't. I think the owners learned from that and will stick together for something they feel will work much better than the last CBA.
And, as you mentioned, it's all about money... Being reasonable doesn't always work when your trying to make money, especially when you are working from a position of percieved weakness...