I know quite a few, and there was a time where almost everyone I interacted with was an immigrant with an H1-B or OPT, though I think all of them did go to school in the US and got hired as full-time employees through the same process Americans would go through.

I also know immigrants who left after a few years, but only one had planned/wanted to do so from the start (and that's just because he didn't want to bother the uncertainty of trying for an H1-B).