I can explain this strawmaning. Marxists does not employ individual choice nor rigid list of do and don't that does not account for the local material condition. Supermarket and grocery shopping are practices that are acceptable under Socialism, and Marxists will support trades until the economy progress to the stage where those market practices become irrelevant. It is unlike the victim blaming ideology of the Capitalists that blames Communist takeover and paranoia fear for scary red conspiracies on the laziness of the alleged "victims of Communism".