I started bringing my own glass jars to the deli to cut down on plastic wrap. It felt weird the first few times, but the workers are cool with it now. I figure I've saved around fifty pieces of plastic from the bin this past month. It's a tiny win that adds up, and I feel good about it.
I used to roll my eyes at stuff like this, but @grace830's bread bag trick got me trying small changes. My local deli actually weighs the jar first now.