It's not just bottles. Manufacturers must register packaging materials they use on their products with a central register and pay fees for all the packages they produce. Since january 2019 a revised form of the law is in force which also applies to packages used by online distributors, e.g. amazon has to pay fees for the cardboard packages it wraps around the manufacturer's pre-existing packaging for which the latter has already paid.

There also are mandatory recycling quotas.