If you look at just the numbers for Kiryas Joel you see that the median household income is 40K. No non-Jews there to skew the data.
The point is that the government obviously does not want to have to subsidize people. If that hippie wanted to have 10 kids than getting a PhD in archeology and anthropology is not going to cut it. So yes Chasidim should not pursue such a career. But being a doctor, lawyer, accountant, dentist, actuary etc. – good clean professions that many frum erhlich Litvish people do will. Yet for that you need college education and a decent high school education before. And if you look at the Agudah Whitepaper they quote a Nishma research paper that shows that the average Hasidic income is 102K compared to what they term “Yeshivish” which is 164K. So Litvish is better off and pashtus is because they have a better education system and many of them become professionals instead of businessmen which is a highly stratified profession in terms of income.