Cannot see the point myself. Either buy the syscart, or make your own base with some wood strips glued on to prevent the systainers from moving around.
These wheel-less SYS-Cart Bases are also meant for hanging to a wall.
Although I would not want to open a systainer which hangs to a wall, because everything will fall out.
Taking the systainer of the wall when closed will work better.
Look at the Tanos information: Tanos
Very strange! What could you possibly put on the wall that wouldn't fall out when the cover is opened? Not even sandpaper or dominos . . . . Strange concept for marketing the product.