yes the measure they are talking about is market cap, not sales. the market cap for Wlmt includes sam's club, walmart.com, etc.
In terms of total sales, Wlmt (including subsidiaries) is close to $500B, while Amazon is approaching $100B. However, Wlmt.com (domestic) is only ~2% of total sales times $288B total domestic sales so only ~$5B sales
In terms of total sales, Wlmt (including subsidiaries) is close to $500B, while Amazon is approaching $100B. However, Wlmt.com (domestic) is only ~2% of total sales times $288B total domestic sales so only ~$5B sales