That’s not totally true. Many small towns are agricultural towns and have a pretty high percentage of immigrants. I’d venture to bet there’s a higher percentage of immigrants in Walla Walla (an AG town) than in Seattle (population center).
Not empty at all, just mostly Federal land belonging to all US Citizens. It's not like there's any more development-type land there to build them free cities to live in. WTF is wrong with your backyard? How many illegals have you stepped up and housed permanently? Learn your country, then post.