Until I see evidence to the contrary I'm happy to accept the Butcher's Boy was crystallised in America and that any British versions are derived from or influenced by the American oecotype. I believe that one British version actually mentions 'Jersey City'.

FWIW my thoughts on evolution of BYS:
The very influential c1840 broadside was derived from the 18thc 'The Lady's Lamentation'. As far as I can see the 'Brisk Young Sailor' first stanza is present in all early versions where the 'alehouse' stanza is also present so they came together as a job lot (along with the 'belly low' stanza). All 3 occur together right into the collecting period in the longer versions so from at least 18thc to modern day.