> Why is it such a difficult idea for the "daemon" writers to accept is beyond me
Because the basic OS interface is a 50-year-old design with "terminals" being the central I/O entity.
Differentiating between "interactive" and "daemon" mode becomes tricky for a daemon writer. In interactive mode, SIGHUP must terminate your process. In daemon mode, you may interpret it any way you like. Same for SIGINT, SIGQUIT, SIGPIPE, etc.