This just complicates the handling of the request on the client for no apparent benefit. And there are many more HTTP codes besides 404 which are mostly meaning

This just complicates the handling of the request on the client for no apparent benefit. And there are many more HTTP codes besides 404 which are mostly meaningless (payment required, anyone?), or fit very poorly within the application logic. It is a layer of legacy cruft that is best avoided. Non-200 codes should indicate some exceptional situation on the server and could be handled client-side as "server configuration exception".