Bettman and the owners are trying to renege on contracts they signed and offered the players in the first place and are locking them (and us) out to do so. If they don't want to pay the players as much they shouldn't offer as much in the first place. It's as simple as that.
The CBA has expired 3x during Bettman's tenure as commissioner of the NHL and he has locked us out every time. He uses it as a negotiating tactic.
The players can't just let Bettman lock them (and us) out every time the CBA expires to get what he wants.
And to all those that say Bettman only works for the owners and does what he wants
He didn't do it on his own, but it sure wasn't the players pulling the trigger on the league's god awful business decisions (overzealous expansion, failure to admit mistakes, failure to properly vet prospective owners, over-sized goalie equipment, crappy television contracts, league scheduling, instigator rule, lockouts every time the CBA expires, etc.).
The owners deserve plenty of the blame for the current mess, but Bettman was hired to manage and run the league. Like shareholders of a corporation, the owners don't really run the league. They may own it, but they have delegated most of their managerial rights to Bettman. In fact Bettman has a severely punishable gag order placed on them. Bettman does make decisions, and these decisions do in fact have consequences.