I used to be part of a group in my area that was buying insulated bags in bulk from a manufacturer. Recently I started using some insulated bags on Amazon. I prefer the Amazon bags. They're three times what I was paying with the bulk group, but they're so much better made. They last me a heck of a lot longer too.

https://www.amazon.com/dp/B00JFOQ10A

The Shipt official bags are a good quality, but I prefer not having a big Shipt logo on the bag.