The British (East India Company) first fought and defeated the Gurkhas in Nthe Nepalese war of 1815. They had such a tough time doing it that the East India Company incorporated them into their private army.

Nepal provides Gurkhas to the armed forces of the UK, India and to the Sultan of Brunei. The deal that the Gurkhas had with the Government of the UK was made with the Government of Nepal. The reason that they were not given the same pensions, etc as the men that they fought alongside in the British armed forces was because the Nepalese Government did not want these men returning home "rich" enough to upset the apple cart back home in Nepal.

My own personal take on it is that they are the best light infantry in the world bar none, having served alongside them in Borneo. Having served the crown they should by right be entitled to British citizenship, with identical pay and pension rights as any other British serviceman. They are contributers to any society or community that they find themselves in and the Crown, the British Government and the British people should be ashamed of the way that these men have been treated.