mcdonalds milkshakes are not actually made with milk and ice cream the way you would do it at home or get it in a resturaunt. they are made from vegtable fat and milk powder, so the two together do not in fact make a milkshake in mcdonalds. due to the fact they are not really milk they are often called simply shakes, that might have something to do with the non availability in spain or it could just be that they removed them from sale because nobody bought them.