Kroger's secret weapon in the battle for your dining-out dollars is ... sushi

• Kroger has quietly become the biggest sushi seller in the US, The Wall Street Journal reported. 
• America's largest grocery retailer sells more than 40 million pieces of sushi a year.
• Kroger wants to become a destination for more than just your groceries.

Supermarket sushi is becoming a mainstay with US shoppers wanting quick, healthy, and easily transported meals. 

Sushi sales at US retailers were up 72% in the past year, according to a report by The Wall Street Journal.