I don't suppose that anyone will be surprised that in my humble opinion and I rather think most of kilt wearing Scotland too, that a flat cap with the kilt looks downright awful. I know someone will chip in with an "Edwardian" type picture to "prove" that caps and kilts were worn together and it's true they were. It did not stop it looking, awful then just as it does now. I am a fan of tweed caps, but not with the kilt. As to those baseball hat things I make no comment.

How and what people choose to wear is ,of course, up to them and it is also their right to look like a lemon, if they so choose.