Question

give reason why plastic container are used as storing device

Answer 1

Plastic containers are cheap, light in weight, easy to handle, do not hurt hands, do not rust, do not react chemically with food items. They are also easy to clean with soap solution and often they are not sticky. They are usually odorless. They can be also made to look beautiful and they can be manufactured in different shapes and sizes.

Answer 2

Plastic container are insulators, where there is less flow heat from the containers to atmosphere and from the atmosphere to the container.
That's why plastic containers are used as storing device.