I pick up my material at a local supplier. I am often loading my truck with the exact same inventory that the other local guys are using. However, more times than not I am paying substantially less for the materials. Also, I would not say that the vendor is making little or nothing from us. They may not be making as much per bag but they do make it up on volume. Once the bid is awarded to a particular vendor we are obligated to purchase from that vendor. If we do not honor the integrity of our buy group we will be suspended from it.