I'm speaking from first hand conversations with H1B's who go on about how their company is holding this or that over their head such as green card sponsorship.

I'm speaking from first hand conversations with H1B's who go on about how their company is holding this or that over their head such as green card sponsorship. You are completely ignored my point that those employers can hire those people in their countries as those employers that you named have offices in every major city around the world. They have big offices with thousands of employees. Your statement about companies wanting to hire specialized skills is pointless. Everybody agrees with that. Your statement about managers not wanting leverage is just not true. What else do you think it means to want to hire to someone other than to have leverage over a person. I made the point that employers want undue leverage when money is not enough and that is why they use H1B.