Here in Ireland we have a return scheme like the one you describe in Germany. It began operating earlier this year and is widely used. I have no idea what happens to the plastic bottles and metal cans after we put them in the RVM at our local supermarket.

I must do some research and find out.

We also have the soft plastic recycle schemes in supermarkets although, unlike UK, it is now acceptable to put soft plastics in the domestic recycling bins. But in both cases it is supposed to be 'clean and dry'. A bag that has contained frozen chips, as a typical example can not be cleaned and dried without the use of hot water and detergent so I confess that we don't bother. I'm not sure if that makes environmental sense or not.

Farmers have soft plastics recycling schemes (for the wrappers for silage bales) and near us there is a plant that converts plastic into fuel. That process has questionable environmental consequences.