Most grocery stores do not charge for the plastic bags you can use to bag your groceries. Assuming the bags don’t tear from pointy objects when being used to transport your groceries, they are sufficiently leak-proof to keep trash cans mostly clean when you put trash in them.
Using grocery bags as trash bags has several benefits:
- It is completely free, so saves the money you would otherwise have to spend on trash bags proper.
- It leads to less waste overall. (Less so if you would not otherwise need to use the plastic grocery bags, such as if you have reusable bags of your own).
- Since grocery bags are small, using them as trash bags forces you to more frequently move trash out of your kitchen (and to an outside trash can, an apartment trash compactor, etc.). Their small capacity is a built-in reminder to not let trash build-up, which can lead to bugs and smell.
I personally use a collapsible fabric crate to carry my groceries to and from my car, so wouldn’t technically need to bag my groceries, but I still do it on occasion simply to acquire the grocery bags for free.