According to the online magazine Wired, the AAA and other sources, the answer is about bureaucracy as well as technology. Many states are wedded to specific providers. (Florida’s marriage to its current contractor, Conduent State & Local Solutions, is not far short of a disaster. The last of bills that piled up last summer are just now being sent. The Department of Transportation admits the new system was “completely overwhelmed.”) Their administrative policies differ as well.