"I think Laycock does 'romanticise'; it is one of the ways he tries to create sympathy, "
I disagree totally
My understanding of romanticising is producing a roseate pastiche picture of the characters and their backgrounds - far from what these writers were - and a thousand miles from the output of the broadside presses
In some cases, their stly may have been borrowed thus their subject matter is nearer to Engles 'Conditions of the Working Class in England' than it was to Harrison Ainsworth
Jag mentioned Harvey Kershaw - a romantic poet, even though he was writing from his own background
I remember seeing him and Harry Boardman perform on numerous occasions and comparing the 'Reet Lancashire' songs with some of Harry's traditional songs - Harry was as much as chalk and cheese as to be two different singers   
Some of these poets were political activists, Bampton being a prime example - it was their activism that inspired their writing, noth their need to put food o the table

It's interesting to compare this song making tradition with that of the Irish over the same period
Both were making songs, the difference being that the Irish had rich and thriving oral tradition to draw from whereas industrial Lancashire appeared not to have.
This is certainly reflected in the songmaking
Rather than basing these arguments on the printed word you really need to judge the songs as sung.

"but I don't think it is accurate to assert that the whole trade in Ireland went like that"
The rural trade did - the towns of course were influenced by the bad poetry of the broadsides
The rural 'ballad selling trade' has been very much neglected and lumped in with the urban one - they really were very diifferent repretoires
Ironically, the ballad trade was almost exclusively the domain of non-literate Travellers, who were also the saviours of some of our best examples of Traditional ballads and folk takes - an almost pure oral tradition
Jim