Why don't people buy tetra packet milk as we can consume it directly with higher shelf life at similar price as packet milk?

Amul has two products - * Regular toned milk (Amul Taaza) - 500 ml - 28 rupees * Tetra packet (Amul Moti) - 450 ml - 30 rupees I see not much of a difference in terms of price. I feel it is better to consume a tetra packet. What are your guys opinion on this?