Rules, regulations, tariffs, taxes are influencing factors.
High taxes on energy drives business to innovate to reduce energy costs.
Packaging is a very hard problem to solve though.
Cradle to grave modelling of packaging exposes difficult issues to solve.
Consumers want their food conveniently packaged. Packaging needs to protect the goods in transit from producer to warehouse, onwards to shop and finally from shop to home. The cheapest, lowest energy material is almost always plastic.