They (and their families) haven't been paying taxes into the community their entire working lives like the natives have. The argument is that the people who have been contributing to the society more and for longer should get to see some benefits from the system before someone who has contributed literally nothing to your community shows up. That's why out of state students pay way more for tuition than in-state students at public universities.

Even if you have some wacky reason for disagreeing with this logic, then take the taxes out of it. What's wrong with caring about your fellow citizens who's vote might affect your more than someone that's possibly displacing them?