After repeated calls during the week from the Kangaroos for a 30,000-plus crowd today at the MCG, only 23,427 showed up to watch them beat Melbourne by 48 points.
Arocca and other club officials had wanted to send the rest of the league a message about North's resurgence, but this time the fans did not respond as hoped.
It was a rare off-field setback for North since their brave decision late last year to reject the AFL's Gold Coast relocation package.
The Kangaroos have reached 30,000 members for the first time and Arocca has earned widespread praise since taking over as chief executive earlier this year.
"We were disappointed, the only encouraging thing was there was more blue and white than red and blue (in the crowd)," Arocca said.
"Conditions were perfect ... personally I'm gutted, I'm sure as a team it was a great result, but we've just got to keep working.
"We've got to keep finding ways to engage our 'customers', if you want to call them that - our supporters.
"We know we've got 30-odd thousand members and maybe the fact it was on Foxtel live, I don't know, I can't imagine that's a major reason - it just highlights how big a challenge it is."
The North Melbourne home game was transferred from the Gold Coast after the club's relocation project fell through.
"It's not going to hurt us (financially), but we were really keen on having some sort of message out there to the rest of the AFL community that with a reasonably good team, on a good day and on a great ground, we should be able to get 30,000 people," he said.
"It's one thing buying a membership, we need support at the ground ... if they think they've done enough, they're wrong."
North coach Dean Laidley also made a point post-match of noting the crowd figure.
"I know we didn't get the crowd that perhaps we would have liked, but from where I was sitting, the majority looked blue and white," he said.
"I'm just pleased our supporters did show up for our boys."
The Kangaroos' next opponents are Collingwood, where Arocca had a long tenure in a variety of roles before switching to Arden St.
"I'm looking forward to it ... I've still got some great friendships at Collingwood," he said.
