We keep the plastic ones for trash bags. When we go grocery shopping, we get paper so we don't have an over abundance of them thankfully. We use the paper bags to put recycling in, or cut them open for when DD is painting, etc.
Keep em. I use them for the bathroom garbage. When we get too many under the kitchen sink, we gather up a whole bunch and take them to the recycling box at Walmart.
I keeo them for bathroom trash bags and to put diapers in and to put the skins from potatoes in and also as trash bags for cleaning out my car or in my room to collect baby diapers throughout the night