The ammunition is being consumed very quickly because villagers living far away started to gather in large numbers, carrying weapons.
In Yemen, or in any Middle Eastern country, there's a peculiar phenomenon: the government forces can't beat the anti-government forces, who in turn can't beat the tribal armed forces; and the tribal armed forces are simply civilians picking up weapons.
So never underestimate the combat effectiveness of villagers with no formal training. Fighting at their doorstep, these armed villagers are the most formidable, at least much stronger than the Yemeni government forces, and certainly not inferior to the Houthis Armed Forces.
The problem Satan faces is spending the same energy dealing with villagers as with soldiers from the Crown Forces. If one doesn't want to be overwhelmed by enemy fire, one has to suppress them vigorously, leading to a dramatic increase in bullet consumption.
