Sometimes this is used for other purposes, as well. For instance, the busybox binary provides a lot of utilities (cp, init, ping etc) all linked to /bin/busybox, which uses the name it is called under to determine which program to run.
(Mtools is a collection of tools to allow Unix systems to manipulate MS-DOS files: read, write, and move around files on an MS-DOS filesystem, typically a floppy disk.)