Well, keep in mind that for every million processed via, say, Credit Suisse in London, several thousand land up in Accenture (or other IT firm), several go to Deloitte (or other consultancy), some more go to Linklaters (or other law firm). Their employees get their salaries that allow then to support their families and then go drink coffee at Nero and eat sandwiches at Pret. Everyone in this chain -- from Credit Suisse via Accenture to Nero are employing people, growing and paying wages.

Now you can go "those high-earning landlord scum" as much as you want, but nobody in their right mind would say that it's better to have a situation in, say, small towns in the Northeastern England where rent is spectacularly low — but so is employment.

If you work in London at all, you get trickle down from the financial services sector. People who work in finance drink in your coffee shop, eat in your restaurant, ride in your bus or taxi, buy things in your shop.

Look at what happened in 2008. Finance caught a cold and the entire global economy including Britain fell flat on it's back. Brexit has the potential to do far more damage over a much longer period of time, but mostly just to Britain. The knock on effect across the country isn't going to be pretty. But hey, if the rest of Britain decides they'd rather like to have a long drawn out recession just in order to stick it to the bankers then fine.