NCD I totally agree with your sentiments, i.e. the IMC/VMC and practical reasons for not reporting a day VMC EGPWS event.
I came across this ATSB info paper:
http://www.atsb.gov.au/media/27543/gpws.pdf But it is more in reference to the previous GPWS not EGPWS and also only refers to main airport activation. However the paper does indicate that reports were made regardless of in-flight conditions!
Also bare in mind that the operator in question has a CASA approval for low-level ops. Part of this approval includes Low Level SOPs and checklists. One of the checklist items prior to operating low level is to activate the EGPWS audio inhibit switch (switch is a supp item particular to the operator). This stops all EGPWS audio annunciations etc while the aircraft is operating low level.
cheers