The feature has proven successful, with the companies claiming that merch shelf clickthroughs are 30 percent higher than other traffic sources, including annotations, links in video descriptions and banner links, meaning more people are checking out creators' merch. If you're a fan of a creator who uses the feature, you'll see their products below their videos on both desktop and mobile.
Teespring is giving eligible creators (they need to be in the YouTube Partner Program and have at least 10,000 subscribers to qualify) access to its designers to help them create products. In addition, the companies are incentivizing creators to add the store to their channels by offering a bonus of $1 (or equivalent, depending on where they are) per item they sell directly through the merch shelf until June.
The merch shelf seems a solid way for creators to diversify their revenue streams, which could come in useful after many faced demonetization due to changes in advertising guidelines. Now, creators in Europe can take advantage of it too.