Yes, customers are encouraged to bring their own bags to Trader Joe's. In fact, bringing reusable bags is a great way to reduce plastic waste and contribute to a more sustainable environment. Trader Joe's values eco-friendly practices and has long supported the use of reusable bags by offering a discount to customers who bring them. If you forget your bags, you can always find a selection of options available for purchase at the store. It is a good idea to always check the current guidelines and offerings on their web page, as policies may vary by location or change over time. Overall, bringing your own bags is a welcome practice at Trader Joe's and is appreciated by both the store and its customers.