The working paper on retail competition is the latest in a series which indicate the likely direction the Commission will take in its conclusions.
Association of Convenience Stores chief executive James Lowman said that the CC had not fully grasped some aspects of fundamental issues, and continued to underplay the competition and choice offered by small stores.
"Issues that are clearly of paramount importance are being overlooked," he told Convenience Store.
The ACS says the CC does not appear to challenge retailers' assertions that the supply chain is competitive, despite independent data suggesting the contrary. It has challenged the Inquiry to analyse why no independent operator has opened a large store since 2000, while the multiples have seen massive development over the same period.
"Evidence of the supermarkets is being taken at face value and apparently not interrogated," said Lowman.