The club earlier this year played its trump card and told Cats fans that it faced extinction if they didn't sign up and buy season seats, but still they didn't respond.
Even three strong wins on the trot have failed to convince fans the club is about to embark on an exciting era, with only about 40 memberships sold before Sunday's game against Fremantle.
The club is now wondering what it needs to do to convert its latent support base into membership before it submits numbers to the AFL on June 15.
``I'm disappointed that people haven't come on board and I can't find any reason why they wouldn't,'' Cook said.
``I think what it's come down to is probably our form in the last five games last year.
``It's the only thing I can put my finger on at the moment.''
The club has about 22,300 members, down from about 25,000 last year, an 11 per cent drop.
``From a commercial point-of-view it's over $400,000 that we're down, that's a net cash figure,'' Cook said.
Cook said the club last year asked its supporters what it needed to do to increase loyalty.
``They indicated that they wanted more games in Geelong, they wanted more Saturday games and they wanted cheaper seats and we've been able to deliver on all three,'' he said.
``But they haven't bought the cheap seats. We've had 580 seats for $60 a season for adults and $30 for children and they're only half full.''
Cook said Geelong fans were baulking at the discount season seats at Skilled Stadium but were buying them match-by-match.
``We can't rely on that because our base isn't big enough. I don't think we're in that stage of organisational development, or club development,'' he said.
For the fifth time the club this week launched a telemarketing campaign targeting past members, but Cook had his doubts that it would translate into membership sales.
``We keep on going out to the public and saying become a member or we'll die and they must be getting sick of it, but that's the reality.''
The club's biggest membership drop off has been in its Melbourne base, where support has plummeted by 15 per cent.
``We've reduced our support in Melbourne by Melbourne people, and we've reduced our support for Melbourne (home games) by Geelong people,'' Cook said.
``Geelong people who bought lots of seats last year in Melbourne are no longer buying those seats.''
He also said the commitment by Geelong businesses to support Melbourne-based home games had dropped off.
The club has three Melbourne home games this year, all identified early as potential blockbusters.
But the first, against Essendon in round one, fell on the Easter weekend and attracted less than 43,000 and wasn't the cash windfall the club hoped for.
The remaining two, against Carlton and Hawthorn, aren't shaping up to be the crowd pullers the club was banking on.
``Carlton aren't playing that well and Hawthorn may or may not play well so our three supposed blockbusters may turn out to be commercial fizzers for us,'' Cook said.
``The real dilemma for us now, forgetting about what we do next year, is do we put all our eggs into trying to get as many people as possible to the games and try to get a few dollars that way, or do we continue to push the membership path. The answer is we'll do both.''