My uses for plastic bags:
1. small trash bucket liners in the bathrooms
2. used to put a couple of extra layers on food going in the freezer for med./long term. Helps prevent freezer burn.
3. when painting a room with brush or roller I wrap the paint brush/roller (no cleaning) in the bag and tie it off. The next day or two later when I'm ready for a second coat I just take it out and use it. Works great.
In the winter when all the use I can get has been extracted, in the wood stove they go for disposal and a few extra BTU's.