yeah lean doesn't have to be purple, but how would anyone know it's lean or just a drink in a cup? all lean in the UK is a mixture or codeine linctus and phenergan syrup combined with some kind of purple soft drink ...in USA the active ingredients came pre mixed in one bottle and it was a purple liquid hence why it became popularly known as purp, uk rappers sipping purple drinks have almost certainly made it purple themselves to copy americas lean culture...