Why are there no Chinese on a displacement hull?

Many displacement hulls have chines. Many boats built of plywood, especially home built, or of steel have hard chines because it is easier to build them this way. It is difficult to "torture" or bend in two directions at once plywood or steel. A hard chine hull only needs to bend each panel in one direction. Any boat with a flat bottom has hard chines by definition. Planing hulls use chines to help increase the planing forces, not because of construction.