John Tudor & Son of Bridgend closed after the outbreak
Families hit by an E.coli outbreak which left one child dead and 150 people ill found it "galling" lessons from other cases were not learned.
Five-year-old Mason Jones from near Bargoed, Caerphilly, died during the outbreak in 2005.
The events caused "lasting and untold harm" to many families, a public inquiry was told.
Bridgend butcher William Tudor was jailed for a year in September after admitting supplying contaminated meat.
The E.coli outbreak became the second largest to occur in the UK, prompting the public inquiry, chaired by Professor Hugh Pennington, which is hearing final submissions on Wednesday and Thursday.
Mark Powell QC, representing the families, said warnings had not been heeded following an E.coli outbreak in Scotland between 1996 and 1997 which left 21 elderly people dead.
Mr Powell said: "It is galling to the families that many of the observations the Sheriff's inquiry, with the substitution of the name of Tudor for that of Barr, the butcher involved in that outbreak, could be written about the 2005 outbreak.
Mason Jones, five, died after eating contaminated cooked meat
"Much of what was said then could equally be said now."
It was as if the report following the Scottish outbreak was never written, he told Professor Pennington, adding: "The families are determined that in 10 year's time, the same might not be said of your enquiry."
The public "is entitled to eat safe food", the hearing was told.
Mr Powell said William Tudor "was motivated by greed and profit" but criticised public agencies for failing to prevent the outbreak by allowing him to continue working.
The hearing heard Tudor "fobbed off" inspectors who were "not thorough enough", and who should have become "highly suspicious" about the lack of detailed records.
The families believe Bridgend County Borough Council gave Tudor the licence to "get away with selling infected meat" and that this ultimately led to Mason's death.
Mr Powell criticised evidence given by the council during the hearing and said they were attempting to "defend the indefensible".
"In South Wales in 2005, a child died and 150 other people were directly affected, and many, many more were indirectly affected, because of the systematic failure of the regulatory bodies to prevent a rogue trader selling contaminated meat," he said.
In previous submissions to the inquiry, lawyers for the families involved have said failures "both systematic and personal" enabled Mr Tudor to operate from a factory which created a 'high probability of risk', and that Bridgend Council failed in their statutory duties.
However, in its closing written submissions, the council has defended its role in inspecting the John Tudor & Son factory.
It said it a "reasonable" decision had been made to allow one vacuum-packing machine to be used at the premises for cooked and raw meat processing, stressing that rules on the issue were "unclear".
Anthony Vines from Bridgend council accepted the "pain, loss and suffering" caused to many families, and offered the authority's deepest sympathy to them.
Professor Pennington's report is expected later this year
However one female observer said: "It's too late."
He told the hearing Tudor gave the impression of being competent and informed and his training and knowledge meant inspectors would have to "catch him out" if he was making short cuts.
Photographs shown to the inquiry have revealed the unhygienic conditions in the factory, with congealed blood on machines and pieces of raw meat left on the floor.
Bridgend council accepted that there were deficiencies in the way its officers worked with the factory to introduce a hazard assessment plan.
But it says that the scheme was introduced on a "softly softly" basis.
Jonathan Walters, representing Caerphilly County Borough Council, said what happened was nothing short of a disgrace, adding: "If Mr Tudor has a conscience...we hope it troubles him."
No date has been given for a publication of Professor Pennington's report, but it is expected later in the year.
He said more evidence has been submitted, but he is now working on the second stage of the hearing to consider the implications of the 2005 outbreak.
An inquest into Mason's death will not be held until after the report is published.