Aside from that, every European country needs to be independent of the EU, because all it has done is hurt for the sake of accruing power and territory.
The EU is a social market economy. That started in Germany and spread by treaty to the rest of the member states.
I found my trips to Wales in the 90's a bit enlightening. The exchange rate was $1.63 (USD) per UK pound. Merchandise in stores was priced about the same in pounds as I paid in USD at home. Essentially, everything cost 63% more for the same goods. I limited my purchases to a subset of items unobtainable in the US e.g. Welsh language music and books.
The impediment to trade across borders is annoying, but hardly justification for ceding sovreignty to the EU.