QFE is used because of...........tradition. No other reason.
As Chilli says. Time to bin it.
Cr*p! It is used because the aircrew
want to use it. The service Military ATC provides is geared to enabling 'Military aircrew to operate safely and effectively, with tactical freedom, etc'. Hence the use of RPS, QFE, QNH, SAS and, if required, QNE! As far as being 'forced' to adopt a certain pressure setting - it shouldn't happen; and the handover to an adjacent unit should most certainly NOT be on QFE.
Aircraft flying relatively low in close proximity to a mil airfield will routinely be placed on QFE in order to make separation with vis/radar circuits easier - once away from the circuits the appropriate RPS(s) will be offered, if the crew would rather use a different setting (a QNH) they merely have to say so!