PET has a lot of great qualities, here are some:

Lightweight- just 1/10 the weight of glass

Great Transparency

Requires less energy to transport

Non reactive nature

Flexibility in design/colour/cap/handle

Safe for food packaging

Longer shelf life as PET has superior barrier properties against CO2

High Shock Resistance

Recyclable

Economical

Safe as PET doesn’t shatter

Sustainable (more and more PET bottles and Jars are made from recycled PET)

Convenient for on the go consumption due to its light weight

There are no carcinogens in the production of PET bottles/jars