Sometimes, the best way to cut down on plastic is to just say no.
It really sucks hearing that, I know, but the DIY way can be thorny and disheartening. Check plastic bags to make sure they are at least recyclable, and if they aren’t (Bear Naked is a strong offender) or recycling them seems really difficult, the best move may have to be to put it down and walk away. On the brighter side, there are ways to work around this! You can make your own chocolatey trail mix without the use of an unrecyclable bag, and you can bring your own reusable produce bags to purchase things like rice and loose tea.
If you do really want something that is packaged in a plastic material that isn’t easily recyclable, try reusing it. Maybe you can store your trail mix in this bag instead of tossing it out, or maybe you can clean it out and keep your electronics in the bag when you go to the beach to keep them dry and sand-free.