Personally, I have no problems with him doing this as like you say, he's from a staunchly Republican family and area. For such a man of principles though, he seems to have no problems paying (quite a lot of) tax to HMRC, knowing fine well that a lot of it is going directly to the British Army......that's where I find him to be an absolute hypocrite.
What's he supposed to do? Quit football to make a tax statement?