"Lots of Scots support England"

Who are you talking to? Because I'm sure I could ask every person in my town and not one of them would support England. It's not being a knuckle dragger, it's not genuine hatred, it's the oldest football rivalry in the world where Scotland have always been the underdogs and wanting England to lose is how it works. You'll get a minority where it's driven by over the top misplaced hatred, but for most it's just a hilarious laugh watching England fall flat on their face after yet again being ridiculously overhyped by their media.

And I know exactly what you're implying by saying people who want England to lose at a sport also embarrass Scotland in another way. I personally think wanting to stay chained to a Westminster government who treat us with undisguised contempt and wouldn't piss on us if we were on fire is the real embarrassment, but that's another topic not suitable here.