Thats the thing, most of us immigrant does not come from well-off countries. We couldn't just book a ticket and get visa to work in , say Canada or Japan. Our passport power is shit. All things considered US is still the most welcoming for most of us who want to improve our life. Where I come from, I can got thrown into jail if they found my religious non-affiliation, combined with my racial identity. Not sure for other immigrants, but for me, companies literally have execution power over my trajectory of my life.