Why is it recommended to have are marketing list with a Smart Shopping campaign?

A remarketing list is crucial for Smart Shopping campaigns because it allows the system to target users who have previously interacted with your business, such as visiting your website or adding items to their cart. These users have already demonstrated an interest in your products and are therefore more likely to convert and make another purchase. Smart Shopping campaigns leverage machine learning to optimize bids and ad placements, and providing them with a high-intent audience like a remarketing list significantly improves their performance and return on ad spend. The other options are incorrect because remarketing lists primarily focus on online user behavior and purchase intent, not necessarily in-store purchases or local traffic in the way described.