H Williams rejected the proposal, and Quinn decided to open a supermarket there himself in December 1966, which became the first shop in the Quinnsworth chain.

That same year, the business announced that it intended to close 7 of its 31 supermarkets in Dublin (in Baggot Street, Blackrock, Dolphin's Barn, Finglas, Killester, Ranelagh and Rosemount).

The Irish Association of Distributive Trades criticised this development as "clear proof that the supermarket giants have now achieved monopolistic control of the Dublin grocery market" and that the takeover of Five Star by Quinnsworth should not have been permitted.

Quinnsworth responded by citing size limitations and a modernisation programme, and countered that it was carrying out a major expansion of its Rathfarnham supermarket that year, and that it intended to open a shopping centre in Artane, to extend its Ennis and Wexford shops, and to open new supermarkets in Tullamore and Navan in 1982.

Quinnsworth was also remembered for its advertising campaigns featuring its marketing director (and later chief executive) Maurice Pratt, who would personally introduce new product promotions, ending each advert with the company slogan, "That's Real Value".

[18] In 1996, Quinnsworth announced that it had taken a large unit in the new Golden Island Shopping Centre, which was due to open in late 1997.

It was anticipated that its existing supermarket in the ageing Athlone Shopping Centre would be rebranded as Crazy Prices.

[19] On 20 March 1997, it was announced that Quinnsworth, including its Crazy Prices outlets, had been acquired by the UK supermarket company, Tesco, for IR£630 million.