Carey Ashwell, owner of the Horse & Hound Cafe and Bar in Masterton, said the new system would be a simpler way of remunerating providers: "I don't think we'll necessarily get any more out of it."
The existing system was "very complicated".
"You have to justify your costs with the [department] and they have a specific formula that they work back through to say, 'that was justified'."
Horse & Hound has 18 pokies.
Trust House chief executive Allan Pollard said if commissions came in, venue payments would still be capped so there would be no incentive, or desire, to promote gambling.
"The Minister [Peter Dunne] himself is quoted as saying it has the potential to reduce overall costs. The law as it stands does not allow any promotion or incentive to gamble."
Trust House knew some people had problems with gambling and it had systems in place to try to identify and help them, Mr Pollard said. Lottery and the TAB were allowed to promote gambling, while gaming machine operators were not.
In the year to March, machine numbers fell from 17,542 to 17,182 nationwide and losses fell 2.1 per cent to $811.6 million.
Mr Dunne last month said pokie operators would be able to earn a commission on gambling proceeds, overturning a clause in the 2003 Gambling Act that banned them from profiting from the machines.
Problem Gambling Foundation spokeswoman Andree Froude said operators had been able to claim only "actual, reasonable and necessary" expenses up to 16 per cent.
Details of the new commission structure were yet to be negotiated, but: "Obviously we've got big concerns ... It could incentivise venues to encourage people to gamble."
However, it was good that a condition under the changes would see 80 per cent of proceeds return to the regional council area in which the money had been lost.