Somerset carries the tradition although now much altered to Carnival and torches gone through H&S. North Kent had torchlit carnivals around October/November at Faversham, Sheerness & Sittingbourne in the 1960s. Probably because Sussex people are traditionalists
. In one of the Times articles it refers to the backlash following attempts to ban Bonfire as Sussex people may not support anarchy but they oppose despotism even more. The right to march in Lewes is in the Town's constitution. The lighting of fires in late autumn does in fact predate Mr Fawkes as parts of Pagan festivals and Hallow'een. I don't think there is a hard and fast answer to why the tradition is so strong, Lewes suffered the Marian burnings but that wasn't unique so maybe a pinch of that, add a bit of smuggling, a bit of "Rights of Man" , a bit of rebelliousness, with a liberal amount of Harveys Bitter stirred in.
What is certain is that it is virtually a religion in Lewes and some families can trace their bonfire roots back 150 years or more with it being cradle to the grave for many.