I use plastic shopping bags for regular trash. I get these when we buy clothes, shoes etc. not groceries. When I forget to bring my own bag to the supermarket, I get (buy!) a paper shopping bag. I use that for cat litter.
We have a blue trash can for paper, a brown one for organic waste (from kitchen and garden), big yellow plastic bags for plastic and cans, a grey trash can for 'regular' waste and glass has to be taken to recycling containers that are distributed about town.
The grey and the brown trash cans are being picked up on the same day - every two weeks. The blue trash can and the yellow plastic bags are being picked up once a month - on different days. Trash is a science in Germany!