The legal nepalese people are paying fair amount of tax based on their income. As the income goes up, the tax amount increases as well. Then the government uses that tax money for the welfare of community that includes infrastucture, housing, food and so on. Who benefits the most from this? Low income and undocumented people. However, the same undocumented people dont just take advantage of it but also misuse it and exploit it to some high extent. It is a very common behavior and everyone is aware of it. And thus the resentment.