Actually in the 80's the Home Service Force (HSF) existed in UK as part of the TA.
Mostly old soldiers or Ex-Cadet forces. Had a reduced training liability and a reduced call out liability (UK only I seem to recall), lower pay rate and reduced training bounty. Their role was to act as Guard forces for home based installations to release regular troops, reservists and TA for wider use. No heavy weapons - just small arms.
Very successful with most TA Infantry Battalions having 1 Company as part of their ORBAT (approx. 120 men/women split as 5 platoons).
of course it was scrapped as a cost savings measure when the TA reorganized in the early 90's. Could easily be re-instated and quite cheaply IMHO.
More info here:
https://en.wikipedia.org/wiki/Home_Service_Force
Mine being E Coy 6/7 Queen's (V)
Arc