A study by the Association of Convenience Stores (ACS) claims supermarkets are systematically obtaining cheaper buying prices than competitors, which distorts competition in the grocery market. This opposes the view expressed in the Competition Commission's Emerging Thinking document that no differential exists between supermarket buying and the rest of the market.
The study investigated more than 300 items sold in smaller and larger stores. It revealed that one in 10 smaller shops cannot buy products from their wholesaler cheaper than they could off supermarket shelves.
ACS chief executive James Lowman said: 'This is the single most compelling proof that there is a severe competition problem in the market and shows how important it is that the Competition Commission goes further in their probe of the relationship between supermarkets and their suppliers.
'We were astonished when the commission's Emerging Thinking suggested there is no systematic differential in favour of supermarkets. This was a reflection of the failings in their early evidence gathering, rather than a reflection of what is happening in the grocery market. Our study reinforces that view and it is up to the commission to probe further and more thoroughly into the evidence.
'This inquiry is a once-in-a-generation opportunity to ensure a sustainable future for a diverse and competitive grocery market. We will be consistent in pressing the commission to be thorough and persistent.'