This year's tour has been overshadowed by fan discontent after headline act Kayne West was pulled from the New Zealand, Adelaide and Perth line-ups.
Mr Smith said organisers were forced to downsize to keep the event in New Zealand, despite overall boss Ken West claiming Kanye pulled out after reading abuse from heavy metal fans on Facebook.
Disgruntled Kiwi ticket-holders were offered a full refund or $20 merchandise voucher.
Sales are slow in Australia too, with Mr West telling the Brisbane Courier Mail the tour was likely to make a loss for the first time ever.
In a last-ditch bid to sell tickets, organisers are offering special deals for the Auckland leg of the tour. Fans can buy five and get one free, or buy a single ticket for $160 without the usual booking, delivery or processing charges.
"It's been hard selling tickets this year," said Mr Smith. "We've been selling that package, you buy five and get one free and we've certainly been selling a few of those."
People who do make it on Friday will still see international stars Soundgarden, Kasabian and Noel Gallagher's High Flying Birds alongside local acts such as Six60, the Adults and Gin Wigmore.
Loyal attendees fear the end of a key fixture on the Kiwi music calendar.
Volume magazine editor Sam Wicks said the one-day event had grown into a "well-oiled machine" since its launch in 1994.
"I think in terms of the big shows in town it stacks up well ... The beauty of the Big Day Out is line-ups that you thought were going to be one thing become something altogether different on the day because there are all these discoveries to be made."
But Jeremy Taylor, of independent Wellington store Slow Boat Records, welcomed the news this could be the last Big Day Out.
He said competitors such as Laneway, a boutique festival in Auckland focused on up-and-coming acts, were a more tantalising option for many.
"It seems to me like [Big Day Out]'s been diminishing returns for a while now in terms of the line-up it's been pulling ... You can't just keep expecting people to buy into a brand."
He said this year's programme was weak and did not appeal to a specific market.
"I think with the discounted tickets people are voting with their feet."