Racks like the Tubus and others that are designed to carry 70 or 80 lbs. are more expensive, plus they are sometimes constructed of more expensive materials. As the others have said, for credit card touring, any of the less expensive racks mentioned are more than enough to serve your purposes nicely. People going on a long self-supported tours, carrying everything, need and are willing to pay for extremely reliable, durable racks that can handle the heavy loads.