Milk can get spoiled quickly, if it is not consumed immediately after drinking it
This is major problem during summer
The person who drinks the spoiled milk will get a severe stomach ache in some cases
So if milk packets are not available, buttermilk is the best option
The fat content in buttermilk is lower and calcium content is usually higher

While the milk bags are fairly effective in ensuring that the milk does not leak, disposing these milk bags, can be a major challenge

Like most plastic waste, milk bags are not biodegradable and can block drains and waterways, resulting in flooding and similar problems. There are some people who are using milk bags for crafting purposes, however in India, these people are limited in number as cleaning the milk bag can be a major challenge after emptying it of all the milk.

Due to high fat content, the oily fat in the milk tends to adhere to the surface of the milk bag, making it difficult to clean it completely with conventional detergents