Not just that, but think of the division of labour

A Soviet canteen was being run by people who wanted to cook, and were being paid a living wage to provide food for their comrades. An American factory worker likely had a lunch prepared by their wife who already had to deal with all the rest of the domestic labour for free, worse if she was working because she'd have to do all the domestic work then actual work, or if not that they're buying it from an underpaid cook in a restaurant who's paid barely above poverty wages