Bad economics is triggering me.
Voting leave, would mean that bank passporting; the main reason the UK finance service is doing well, would disappear decimating the Finace service, which right now composes around ~10 to ~15% of UK's GDP. Hamburg ( I think that's called) would gladly accept the role the UK is leaving behind. And if you wanted it back then you would have to accept all of the EU's policies as if you had not left.
I don't know if this video has been posted already, but here it goes: