Here's a scenario: You sign a player at age 30 to a great cap hit, but it's an 8 year contract. The team profits because it gets a player for less than market value and the player profits, because he has long term security. Now obviously said player's ability will drop towards the end of the contract, which is not at all unexpected. But now suddenly the team wants to get rid of him and waives him. So now the player, who signed a team friendly deal, has to ride busses in the AHL to get his money. I can understand players wanting insurance against that.
And again, I find it very strange to blame the players for stupid owners giving out NMCs like candy. They are not forced to do it and if it is a winning strategy to give our fewer NMCs, then maybe some teams should start trying it.