The FAA, more than any technical reason, explains why SpaceX bought two oil rigs to perform oceanic launches.
Many aspects of SpaceX's rockets are covered by ITAR, which puts strict regulations and controls on the exports of many aspects of SpaceX's vehicles.
I imagine exporting the rocket to a non-US based firm would be a much larger bureaucratic hurdle than getting FAA approvals.
This leaves me (and hopefully you) wondering what ITAR actually still accomplishes. I guess federal contracts dictate the use of the ensuing technology? I still see issues with that depending on how IP rights are assigned.
I guess we're waiting on the next PGP-style test of export control laws.