Volunteers(especially at the early stage of war) were not-too-well supplied....BUT-i was talking with some ww2 vets,and they told me militia and also naval infantry,especially during battle for sevastopol had used self-made/scavenged "grenades/molotovs"from whatever they found or took as a trophy from their fallen opponents...this was varying from shattered glass hg to molotovs to improvised fragmentation hg made from junk metal etc..
So-my suggestion is-remove munition cost from cons molotovs and NI and add like longer cooldown-like maybe 90 or 120 seconds.