Last night, I popped into a Trader Joe's I'd never visited before, in the Pompton Lakes/Wayne area of Northern New Jersey. I was pleasantly surprised that I could purchase an insulated shopping bag for carrying freezer and refrigerated items instead of just the canvas bag I'd been carrying. Additionally, the bag is sizable enough to carry more than a typical paper bag of groceries, and you can hook it over your shoulder!
Mind you, I'd been to the Trader Joe's in Florham Park, New Jersey earlier in the day, and they did not yet have the insulated bags, just the laminated shopping bags -- nice themselves, albeit not insulated.
The insulated bags are $1.99 a piece and the laminated ones are $.99 each. What a deal for not using more plastic/paper bags every time you shop!