I've largely had this experience. It was more expensive, added levels of management difficulty, and introduced other intangible challenges. It wasn't some nebulous corporate "greed" it was the fact that we could not find enough candidates for certain roles in the US. Finding local talent wasn't really an option in a lot of cases. I head hunted at colleges, sponsored paid internships, advised on courses and classes that would place someone at the front of the line for our jobs.

The bigger travesty is when we wouldn't promote internal candidates with tons of institutional knowledge, good performance reviews, and drive (regardless of their immigration status). The company always caped their salary expansion or always refused to match external or internal offers. Those people rightfully left for better paying jobs taking their experience and internal knowledge with them. We would then hire some green recruit who we would spend thousands onboarding and training for more than the previous employees ask because we had to hire within industry pay bands. In my experience, every single person that asked for an increase or match ended up leaving, so it wasn't a bigger picture numbers game. If anything, it encouraged other workers to seek employment elsewhere.