The grocery wars have been on for some time, but things are heating up. Last week, discount grocer Aldi announced plans to open 900 additional stores in the U.S., while low-cost grocery store Lidl made its stateside debut. Highlighting the damage this could inflict on incumbent grocery players, a recent report from Oliver Wyman shows that 39% of respondents, all based in the geographies where Lidl is opening its first U.S. stores, said they would shop at Lidl once a week or more in the future — even though they have never before stepped into one of their stores.