Re: free trade: agree that there exists no "pure" implementation of free trade.
Theoretically "free trade" is good on a whole. I give you the converse scenario:
Imagine that you split up a big country (e.g. Russia, US) into small constituent states and they can levy tariffs and have different regulations from one another. You need to sign customs papers and pay special tariffs to sell across states. What would the impact of that be? Probably negative on an economic whole, but some people might benefit slightly.
Merging countries into a free trade bloc is the mirror-image of that, which is why the European common market is such a powerful idea and the UK doesn't want to lose it despite wanting to leave the EU itself.
A large part of why the UK voted to leave was because of free movement of labour specifically. They didn't want that. They wanted free movement of goods and capital but not labour.