Liability issue, first of all because of salmonella, they can cut costs on hygiene because it's gonna get pasteurized, then you want to have fresh milk in the fridge for few days, then it is deliever from all parts of US and it seats on the shelves. Raw milk stays sweet for about two days, than it goes into curds/kefir ( iam not sure I used right word here). So you would have to go to the grocery store every other day, and that's what people do in some parts of Europe, because besides large supermarkets they have small stores on the corner, where you can buy fresh milk, fresh bread, fresh fruit on everyday basis.