The bakery supplies shop i usually go the boss says these are actually the same as the normal ones u see in supermarkets but these are packed for food manufacturers so its more cheaper.

compared to the blue colored full cream milk.

Just Milk is a different category

Yes u wont see it in commercial hypermarkets...These are sold directly to food manufacturers and shops that specialty in producing food for consumers such as bakery shops (also bakery supplies shops) or coffee shops and etc.

Yes can be drink straight although the bakery supplies seller says might taste slightly different abit.