These initialisation codes are not visible to the user, and are always included by Harmony - it takes no effort at all.
It is when you DON'T have them in the file that the user may have problems. These can include incorrect instruments, wrong pitch, and a number of other faults.

A great many of the MIDI files found on the net do NOT have these codes present, which means that most people who create the files are unaware of the problem, or using software which does not provide the facility.

An inexperienced user may not be able to identify and correct the fault, so it is better to be safe.