First off, the talk of diluted talent is a weak arguement. I think the rough content of Canadian born NHL players right now is about 400. During the heydays of the offensive era of the 80's and early 90's before expansion, there were only 21 teams in the league. I'd have to see the numbers, but, I'm willing to bet that the number of Canadian players in the league at that time was also roughly about 400 (roughly 80%). Presumably, all the European and American players that are in the league today are in the league because they are better than the 401st best Canadian player. So, if our standard for being good enough during the 80's was that to make the NHL, you had to be better than the 401st best Canadian hockey, and, today, that same standard holds true, how can the talent be diluted? The only way is if you believe that today's top 400 hockey players aren't as talented as the top 400 from 15 years ago, and the league should contract because of it.
Secondly, the talk of "marginal franchises" is silly. If the team's owner is making enough money to stay in that market, how does it hurt the league to have him there. Each market gives the NHL more exposure, and a broader fan base. It gives the NHLPA more jobs.
If the market is truly not feasible, it will die on its own. We likely won't be seeing that any time soon though. Teams that are being put up for sale are having success finding new owners. The people that matter seem to think that these markets are viable.