Ms Sanders said the thefts had cost her about $1500 so far, but the real cost was that without billboards people wouldn't know the concert was happening and wouldn't buy tickets.
Most of the billboard, which measure 2.4x1.2m, had been stolen just before Anniversary Weekend when she had hoped to catch the extra visitors using Northland roads.
"The reality is that if we can't sell enough tickets to these concerts then we can't afford to keep bringing great artists and events here," she said.
Putting on a big concert cost a lot of money - hundreds of thousands of dollars in the case of last year's UB40 gig - but they also gave a significant boost to Northland's economy.
More than half the audience at the UB40 concert were from outside the Bay of Islands, who then spent money on accommodation, restaurants and cafes. Ms Sanders said she also spent a lot of money locally on marquees, toilets, fencing and staff, while the vineyard owners had invested heavily to build a world-class venue.
Future concerts at the winery were being put at risk by the actions of a light-fingered few, she said. She did not have any problems with vanishing billboards anywhere else in the county.
The Bob Marley NZ All-Stars band brings together members of Katchafire, Kora and Supergroove, along with Warren Maxwell (Whangarei), Jason Norris (Kaitaia), Tiki Taane, Boh Runga, Annie Crummer and Anna Coddington.
Ms Sanders said the Hawke's Bay show before Christmas was a sell-out with the audience performing a haka for the band after the finale.
- Contact the police or Ms Sanders at jackie@jacman.co.nz with any information about the thefts.
