The same can be said about illegal immigrants and temporary visa holders in the United States. An H1B worker pays taxes, pays into social security, etc, but isn't going to get a penny back out of it.

And yet, for some reason, a lot of people really dislike[1] H1Bs...

[1] Last election cycle, I've received a beautiful election pamphlet from a frothing-at-the-mouth state politician-want-to-be who spent most of his 250 words assuring me that H1Bs are robbing the country by mooching all of its services while not paying any taxes. He, uh, got 40% of the vote.