Why is it such an obsession for them? They're opinions on things are what even a child should have grown out of. It's the most divided country in Europe. The size of the place would suggest that it's a compressed country so it's likely they'll be a wide cross section of people with different opinions in a small area.
There's also status issues happening. They feel less adequate and physically attractive so they'll want to distance themselves from certain things in order to maintain a better image.
They'll want first refusal so saying "No' gives them more control over a situation if they feel less attractive.
As far as money and wealth goes, even when they have what they want there's still a sense of jealousy that they don't grow out of.
They're highly image conscious judging a book by it's cover and not always getting it right.
In Scotland it's always somebody else's fault. Even if they lived in space they'd still blame the english govt.
Because they're not well travelled or tend not to leave the country as much as other nationalities, they're forever trapped in the same imagined opinions on what they think the rest of Britain and the world is like. They're permanently resentful at things that don't exist.
Because it's a small country of only 5 Million they're on a permanent recruitment drive to band together, make up the numbers and usually get the English. Anyone who strays from this group is showered in homsexual slurs. Probably because it's the worst and most annoying insult they can think of which brings to mind how person of low status would act.
There's also deflection to think about, if your concerned or embarrassed about your own orientation then it's likely you'll be wanting to make others feel as bad or will use slurs and insults that would describe yourself.
on a side note: It's usually likely that visitors from other countries, mainly U.S. who have no class system and feel adrift at times will initially side with this type of people and way of thinking, it's easier for them to gravitate towards working class / low status Scots who usually hang about in larger groups, strength in numbers. If your a stranger, you'll regard these people as characters and inclusivity, whether they mean it or not it's welcome if your not from the UK.