Reality is the city of Liverpool is in the majority, anti establishment. What that shower of wet wipes have done is move it from a political stance to an, as usual, marketing stance.
I don't boo the anthem, I don't sing it. Not my king etc.
But there is a hugely historical set of reasons for this city being anti establishment, like Churchill sending watships up the Mersey, Thatcher and Ingham etc etc.
The establishment have always took on this city because it stood up for itself, and more importantly, for others.