Well, I know many people who have used the H1-B visas for exactly that, to stay and become US citizens.
Perhaps you do, but your personal interaction does not a justification make... show me the statistics of those who have taken their H1B and turned it into a citizenship... it is an infinatesimally small number. Most come here for the "big money" for a few years, and have no intention of immigrating. In fact I know of only 1 person in my life that came here via H1B and naturalized... nearly every one I have ever spoken too has no intention of staying or immigrating.