Even if the village of Piddington was serious about becoming a property of the USA, the EU would never let it happen. They would use the same tactic that worked vs Brexit, keep the upstart in the courtroom, reacting to various penalties and fees on top of unpaid fees.
Lather, rinse, repeat until your opposition has simply run out of public funding or invented taxation. In other words, Lawfare, as we now understand it here in the states.
If our Canadian friends in Alberta want to declare independence, this technique will be used on them too.
I agree that the EU would not like it if Piddlington voted to become independent or even a US territory. But what legal issues do you think the EU would be able to raise? Britain is no longer part of the EU.
UK on the other hand...