The entire point of the EU as an entity is that it allows people to move everywhere that companies and services can move to.
Additionally, the entire problem of the refugee crisis was that countries controlled their own border – and everyone refused to do anything, instead telling Greece to prevent them from entering, and Greece said they’d just open their borders. In fact, the EU only got control of the borders in September 2016! http://www.consilium.europa.eu/en/press/press-releases/2016/...
A union needs free movement of goods, people, and resources; or a resource-sharing system, to ensure it stays fair.
That’s why free-trade agreements usually contain lots and lots of limitations to prevent it being actually free trade – and why the agreement Britain wants can never happen.
Your CAN have border control right now, in fact many northern European countries have border control among themselves today.
EDIT: I can’t respond to your comment, but please read the article.
Its just that not having border control is cheaper and allowing people work across birders is good for the economy. So basically until late 2016 the pros outweighed the cons.
The whole reason Brexit happened is because Britain wants to implement border controls.
Edit, Proof: http://www.telegraph.co.uk/news/2016/05/03/eu-to-fine-countr...
Just get rid of these fines, and quotas, and give people control of their borders back.
Blaming EU for your own officials incompetency is soooo uk-2016