Have been through it, and yes if you are not drafted or tendered sorry it is a money grab.
Actually I knew some good players that were even drafted and it didn't work out. Nothing is guaranteed.
The problem is the numbers - most teams have too many players and not enough open positions. So if your player is a can't miss superstar then sure they'll make room. But for most others, its not worth it if your not approached by them first with an offer.
And even if they offer you an NCDC contract, what spot are you being offered? Do you want to be the 13th forward when they dress 12 and play 9? Or the 8th D when they dress 6 and play 4? Or the 4th goalie? Do what you want, but if they do actually offer you something please read the contract fine print and more importantly read between the lines. It might just be better to play tier3 somewhere.