"I can name at leaxst 6 older peopl at my club who are staying in the game because of anchored putters."Mark Johnson is right. While anchoring might not attract new players to the game, there is no doubt in my mind it does keep older players, many of them very highly skilled, in the game and it allows them to compete at a highly competitive level.
One of the reasons Sam Snead was able to compete on the PGA Tour well into his 50's was that he found a way to putt decently by abandoning the traditional style of putting. I certainly feel the best interests of the game were served by having Sam Snead remain competitive and playing in front of the public when he was in his 50's, 60's & 70's.
Is there any doubt that having Fred Couples in the hunt at the Masters over the past few years has been good for the game, regardless of whether he was using a belly putter? Would the Champions Tour be as interesting if Langer, Kite, O'Meara, etc. were not competing on it?
While anchoring may not "grow" the game, it does keep it from shrinking.