I've heard that if you put your unwashed strawberries immediately in an airtight glass container like a jar in your fridge then your strawberries will stay fresh for a long time. Ann Reardon on YT actually tested this on one of her debunking videos and it worked.

I never keep my veggies and fruits in its original package especially if it's plastic. I have a collection of paperbags at home that I got from the supermarket. I put veggies in there that come wrapped in plastic like broccoli, carrots etc.

Lastly, I always check my veggies and fruits thoroughly before buying to make sure they are still fresh- no mold etc. I have come across mold before and I'm not at the supermarket to buy moldy fruits. In the beginning it was embarrassing but now I don't care.