Officers have now issued a CCTV still of a man they wish to speak to in connection with the investigation.
The alleged offences happened at several Bookmakers Shops in the Whitefield and Prestwich areas on the 2 and 4 October 2012.
Detective Sergeant Dave Sinclair, of Bury CID, said: "We have circulated a very clear CCTV still of a man we want to speak to in connection with this investigation.
"I would urge people to look at this picture very carefully and if you recognise this man, then please call us.
"I am also asking local businesses, particularly bookmakers or pubs with fruit or gaming machines to look at the image and if you think you see this man in your premises, please contact police immediately."
Anyone with information should contact police in Bury on 0161 856 8213 or the independent charity Crimestoppers, anonymously, on 0800 555 111.