Nationalists Turn Unionists

I can't help remarking on the bizarre somersaults of the SNP as they try to argue for Scots independence without being independent.  The latest of these is a demand for a UK currency union.  The SNP argues for this using a series of fundamentally unionist arguments about the integration of Scotland with the rest of the UK, the amount of trade between Scots and the English, and so on.  These are valid, and I have mentioned them before, but doesn't it make you wonder why the SNP argue for independence at all?