Problem is its not that simple. You have things like contracts that are negotiated that will still need to be paid ( you honestly think cities are just going to let you off the hook after building you an arena you promised to use for 25 years?), the number of players goes down, which means less jobs and ticking off the NHLPA. Then you've got to deal with the egg on your face from advertisers, media, etc. because your league is shrinking, thus not grabbing as large of an audience, and so you are worth less to them.
Contraction sounds easy, but its not as simple as just boarding everything up, and moving the players to another team. Basically if you are the NHL it means you've given up on the idea of being a nation wide product in the US and are content with being a regional sport. I would like to be a fly on the wall for that owners debate.