Why is the Yakult bottle so small?

Despite the huge demand for bigger doses of this cultured milk drink, however, Yakult still comes in a very small serving -- not even half the size of a cola can -- and it has been like this for over 70 years. 

 So why is the Yakult bottle so small? According to data from Yakult's companies in Malaysia and Australia, the cultured milk drink only comes in small bottles to avoid contamination. In other countries, Yakult is sold in 65-ml and 100-ml bottles. Yakult has only one flavor in all countries across the globe, except in Singapore where it's sold in 3 more variants -- orange, grape and apple. "A smaller bottle is more hygienic. A larger bottle that is not finished might be kept open, thus a bigger risk of infection with other bacteria," Yakult Malaysia said. 

One small bottle is enough to keep people healthy each day so there's no need to sell Yakult in bigger servings, the Yakult Australia and Malaysia said. 

Source: http://www.abs-cbnnews.com/lifestyle/03/12/10/just-curious-why-yakult-bottle-so-small