These carts are used to take children to and from school. From the looks of this one, it probably fits three or four on each side. Being a taxi service for school children is a steady job for a rickshaw puller in Varanasi. Often, it is hard work and the puller will have to dismount and push the cart up hills and over dirt roads. In the summer it can be quite taxing. As can be seen, these carts have roofs to protect from sun and rain. Here's an interesting article on the history of the rickshaw around the world.