RACQ has backed the ACCC's concerns that have escalated out of control, with offers of up to 45 cents per litre (cpl) potentially quashing competition.
RACQ executive manager public policy Michael Roth said the shopper docket scheme could not only affect the retail margins but also affect the independent retailers' ability to compete in the market.
"In 2012 we called on the ACCC to launch an inquiry into shopper docket discounts and we are looking forward to the public release of the results in the next few months," Mr Roth said.
"The latest discounts offered by supermarket giants Coles and Woolworths have underscored the pressing need for the outcome of this inquiry.
"While we acknowledge that many of our members take advantage of the shopper docket discounts, we're concerned the discounts might result in excessive domination of the market by Coles and Woolworths and lead to more expensive fuel for those not using the dockets."
Mr Roth said the shopper dockets originally offered 4cpl discounts but they had since climbed up to 45cpl, which was expected to have a negative impact on competition in the market.