This meme is about self service checkouts which are ubiquitous in my country.
Walmart had an operating profit margin of 4.2% in their last statement, and a net profit margin of 3%.
If you're looking for someone to blame for widening wealth inequality, profit margins under 5% are not where you'll find it. Check the facts instead of going on pure vibes - company accounts are public and subject to audit (on pain of huge punishments if wrong - they got Al Capone on tax fraud remember)