Why is our government allowing so many elderly Russian and Chinese to enter this country & live off Medicaid?

I live in a HUD-subsidized building, which is at least 30% elderly Russian and Chinese. Common sense tells you that they have never worked or paid taxes in this country, yet American born taxpayers have to wait years to get into a building like mine. They won't even try to assimilate or learn English. They don't patronize American stores or shops, as they have private buses to take them to their ethnic shops. Many of them are thieves; the lamps in our lobby had to be glued to the tables to prevent theft. A TV set was stolen off the wall. Door decorations disappear. Their visitors have been seen sleeping in the lobby, and some Chinese cook for restaurants with HUD paying their electric bills. They know how to milk the system, with the government's blessing. Management just ignores these things and kisses up to them, as though they were assets! When $20.00 vouchers are given out for produce, you get in line behind 20 Chinese. They are obviously given a call ahead of time. Why?