Her five sons, led by Sam Steinberg, grew the company from a tiny storefront on St. Lawrence Boulevard into the most popular and largest supermarket chain in Quebec.

Steinberg's entered the real estate market in 1952 under the name Ivanhoe Investments and owned several shopping centres.

Store outlets could be spotted in nearly every district of the island of Montreal and was a major competitor for chains like Provigo and Metro.

By the end of the 1980s, family infighting, power struggles, rising costs and increased competition were taking their toll, and Steinberg's was placed on the auction block for an estimated $1.5 billion.

The Ontario-based Loblaws chain attempted to acquire Steinberg's, but was blocked by the Quebec provincial government on nationalist grounds.

Other potential buyers included Toronto-based Oxdon Investments, Oxford Development, Metro-Richelieu, Provigo, and a leveraged buyout from company executives Irving Ludmer and Arnold Steinberg.

In the end, the company was sold for $1.3 billion on August 22, 1989, to a joint bid between Socanav (a marine shipping firm with no experience in retail, and whose major shareholder Michel Gaucher helped set up the deal) and the Caisse de dépôt et placement du Québec, Quebec's pension-fund manager.

Despite improved profitability and cash flow results from Steinberg's after the buyout, various parts of the company were auctioned off by new owner Socanav to help pay down the heavy debt load incurred.

The Caisse de dépôt et placement du Québec wanted Steinberg's real estate arm Ivanhoe for its attractive portfolio from the start, and acquired it for $887 million in 1990.

The stores continued to operate under their former names, but were eventually rebranded under the "A&P" and "Dominion", and Ultra Mart/Ultra Food & Drug banners.

Attempts to sell off more assets and restructure the company (including rebranding some stores and franchising others) were difficult, due to Steinberg's higher labour wages, the 1990–1992 recession, suppliers unsure of supplying the highly leveraged company, pressure from creditors, mounting losses and interest payments on debt from the leveraged buyout.

They were again foiled by the Quebec government, who arranged for Steinberg's stores to be sold to its two major local competitors Metro Richelieu and Provigo.

Most of Steinberg's grocery stores were absorbed and converted by its competitors, while the M locations closed outright as no buyer could be found for them.

Succession for the Steinberg's grocery chain was the subject of a 1974 National Film Board of Canada documentary by Arthur Hammond entitled After Mr.