The US government is intentionally "schizophrenic." Immigration law is set by the Feds, driver's licenses are up to the states, and there's no particular reason those distinct entities have to align their views in their different areas of responsibility.
"No particular reason" except for an expectation that the outcome be sensible.
See, you can make the argument that "this is how it's organized" all you want, but when the outcomes don't make sense it just morphs into "why is it organized like this".
