How much is a vote on same-sex marriage worth?
An Australian has offered to sell their survey at a starting price of $1,500 on eBay.
The seller said they had no desire to fill out the form and would donate some of the money to charity.
"What is this plebiscite worth to you. The reason I'm selling my vote is because either way I don't care but thought there are people who do," they wrote on the auction site.
Australians for Equality campaign executive director Tiernan Brady has urged people to take the survey seriously.
"What an idiot."
"What do you think you're doing? This is a serious discussion about real people's lives," Mr Brady said.
Australian Christian Lobby managing director Lyle Shelton echoed Mr Brady's sentiments.
"There are always going to be people out there who do silly things, and this really does trivialise what is a very important decision for the Australian nation," he said.
Auction sites confirm survey listings violate policies
In a sign the Australian Bureau of Statistics is concerned about people selling the survey, it has been in discussions with online sites, including eBay, Facebook, Amazon, Alibaba and Gumtree.
"To date, eBay and Facebook have confirmed listing survey forms or survey responses for sale would not comply with their policies and they will block and remove any such listings," an ABS spokesman said in a statement.
The ABC contacted the seller to try and verify the post but was yet to receive a response.
An eBay spokeswoman confirmed the listing had been removed.
"eBay has active processes in place to filter for issues like this," she said.
South Australian senator Nick Xenophon said the post showed how the voting process could be abused.
"Any attempt to game the survey, any attempt to distort the results of this important survey must be met with appropriate legal safeguards, otherwise it makes a complete mockery of it," he said.
12 months or $2,100 for bought or sold responses
The Australian Bureau of Statistics insisted it had appropriate measures in place to stop people rorting the system.
"The ABS considers the submission of any Marriage Law Postal Survey Form with a response that has been bought or sold would likely be an offence against the Census and Statistics Act 1905 or the Commonwealth Criminal Code," a spokesman said.
"The offence against the Census and Statistics Act 1905 carries a maximum penalty of $2,100. The Criminal Code offence carries a maximum penalty of 12 months' imprisonment."
Mr Shelton said he had confidence in the integrity of the system.
"We have been briefed on some of the integrity measures they have put in place and I'm very confident this will be a process that all Australians can have confidence in," he said.
Prime Minister Malcolm Turnbull did not directly address questions about the eBay post, but again called for all Australians to be mindful of how they engaged in the same-sex marriage debate.
"You cannot expect your side of the argument to be respected unless you respect the other side of the argument," he said.
The ABS will begin mailing out the survey on Tuesday, September 12.
