That's absolutely why they are there. The US grid has very limited capacity, and expanding it will be a decades long project. It simply cannot support a significant data center build out in its current state. Yes, they do build data centers in the US, but there is a hard limit on the available energy production.

Putting data centers in these vassals states basically ties them deeper into US economy, and ensures their oil goes towards powering American data processing infrastructure. There's a great discussion with Michael Hudson on the subject incidentally. https://www.youtube.com/watch?v=xHvpgCaCkSs