What's interesting is that there is actually more Fortune 500 companies in the EU (though really just in western Europe) than in the US. However the difference, I believe is that till now political power is less concentrated in the EU than it is in the US so Shell has much less influence on most EU states than Chevron has on US states simply because it is harder for Shell to influence policy outside of the Netherlands and UK. But with the harmonisation of markets and EU policy and centralisation of political power this will all change.
But I see your point. It's not American interests against European ones. It's to prevent a secession in a geographical space more and more dominated by some corporations and financial institutions. A secession would make it a little bit harder for them, but not so much IMHO, unless it spreads and the EU shatters (maybe because of the migrants crisis.)
https://www.splcenter.org/hatewatch/2015/08/07/getting-cucky...
http://fortune.com/2015/08/27/tech-manufacturing-relocation/
Korea isn't all that cheap either, probably roughly equivalent to the US.
What saddens me more is that the cucked EU will let them, forgetting all the achievements this continent has to offer.