知らないうちにこんな内容のrtfファイルがあったわけだが…

This installer will create a directory in /Applications/ for local files (if applicable) and install the application and support files in the appropriate places throughout your system. Binaries are usually installed in /usr/local/bin/

Application Notes:
nethack is installed in /usr/games/ and is normally run as the user games. See /usr/games/doc/ or nethack.org for more information.