You are over analyzing IMO. These people receive new aircraft on a regular basis and considering the cadet program will only feed them 30 pilots a year they need other ways to staff the airplanes. I also believe it's easier to convince an American pilot to leave his regional company and go for the big irons, easier than in Europe. They also did that in South America. When flying to my assessment from Madrid, I flew Lan Chile. I happen to know some people in the company so i stepped into the cockpit to say hi. I remember the captain told me that various middle eastern companies had gone asking almost every captain, if they wanted to join the company.
These companies offer such a great package, it's not hard for them to take pilots from other companies.