You should blame them and still choose options with less plastic where possible? I don't see where this idea of black and white, one or the other comes from

Where it's feasible given your financial and geographical means, avoid food wrapped in plastics, foods shipped from far away, and meats. Not every single item in the store comes in plastic. It will require adjusting your habits, for sure.

No need to demonize anyone for not being able to if it doesn't work, but every time you choose something better, it's an incremental step forward.

At the same time, send an email or phone call to the grocery store manager. Write to your local politician and push for laws regarding stricter use of plastics, more comprehensive recycling programs, or funding and grants for local farmers.

Simply being angry online and not changing your own habits or lobbying for change isn't actually improving anything.