It's only double discourse if you assume that they actually meant the whole world rather than 'America, Canada, Australia, New Zealand and the white bits of South Africa' which would mean ignoring the pictures they used of a Muslim family sneaking under some barbed wire (apparently in an attempt to get to Europe) alongside their scaremongering about Turkey and other 'poorer countries' joining the EU.
But that's the thing, it's not Ukip that holds power and even among Ukip it's not people with societal concerns that hold the power. Just look at leave main financers, they are all finance people they don't live with these foreigners and don't care about them, they might not like them but they will try to make money with anyone, they will always go to the option that creates the biggest margin. They only care about the money part, not the social side of things.
You have an actual example in Jim Ratcliffe who was/is a support of Brexit but moved to Monaco, Monaco is effectively an extension of France and the rules that applies there are generally negotiated with the french government who according to leavers doesn't have power and is subjected to Brussels. The man has no principles, he only cares about the tax free conditions that Monaco provides.