They also sold fewer deluxe corporate boxes than they had budgeted for.
Organisers had relied on fans surging through the gates to turn a profit, but instead they now find themselves staring at the prospect of a sizeable loss.
A source close to the organisers said the loss would be at least hundreds of thousands of dollars.
But other people at the tournament suspected it could be much higher, perhaps more than $2 million, based on the crowd figures.
Open 2002 managing director David Pool yesterday assured the tournament's creditors that they would get their money.
Many of the main companies contracted to the Open were pre-paid, he said.
Corporate Host managing director Ian Fraser, who was in control of the catering at the Open, said caterers would be paid.
"The caterers and beverage people will get their money."
Another creditor said it was common for sub-contractors to require early payment for special events because so many had been burned before.
"We got our money upfront. I'd be surprised if that's not how most of the others did it too."
Mr Pool said there would be no attempt to dodge creditors, and that the event company would not be liquidated.
The major unpaid bill left from the tournament remains television production. Mr Pool said he expected it to be paid this week.
The event gained its income from investors' money, sponsorship, corporate hospitality sales, gate and merchandise sales.
He said a dozen private investors, all from Wellington, had put up between $200,000 and $1 million each and would not be asked to dip back into their pockets.
Mr Pool said he believed directors of the Open had all acted prudently in putting the tournament together.
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Full coverage: NZ Golf Open 2002
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