The difference is in the quality of the printing achieved between the two products. Its quite a significant difference, however the up side to the Shade Cloth is that it is very affordable and does the job. It also lets more air through so it creates less wind load on the fencing.
Banner Mesh offers a premium looking finish, right through to a full coverage print. The lifespan of the Banner Mesh is greater due to heavy weight construction of the base material, along with the rope edge for added strength when attaching to the fence.