It's just decoration. Filler for the curved design. Deebs can adjust the colors and styles to suit various products. But keep in mind, it's got a square aspect ratio, 1:1. This isn't the best fit for longer items like towels. It's not a deal-breaker, but stretching it to cover a towel would look cut off. Square designs are great for stuff like apparel, mugs, and coasters, though.
I've also worked on some designs with a vertical aspect ratio, which should work better for towels and posters. I'm planning to put some of my extras in an album soon. Deebs is welcome to use any of them in the store if people like them.
When you try and stretch this is what happens: