Iqbal,

If you had hundreds of thousands of donkeys or camels running wild, you would hunt them too.

Camels were brought here from your neighbourhood, NW India/Pakistan/Afghanistan for use in the building of telegraph lines and railways in the desert.

When no longer needed they were released.

Donkeys were brought in for similar purposes, freight carriage, mining use etc. Again many escaped into the bush or were released when no longer needed.

Running feral, they are now a pest in large numbers, but also a fun hunting target. Donkeys are not challenging to hunt, but still some fun.