Thatcher's disastrous de-industrialisation policy, which disproportionately affected large swathes of the country (not just the north incidentally -- South Wales didn't have a good time of it, if I remember correctly) is not "discrimination" in the sense of racism or anti-gay discrimination, and...
Clearly it's an issue, and at the risk of stating the blindingly obvious the reason it's different from chants about northerners or wurzels (but similar to racism), is the simple reason that northerners etc haven't been subject to systematic and pervasive discrimination in society as a whole...