Scrounger's urge to be in pub (6)
I believe the answer is:
beggar
'scrounger's' is the definition.
(thesaurus)
'urge to be in pub' is the wordplay.
'urge' becomes 'egg' (I've seen this before).
'to be in' indicates putting letters inside.
'pub' becomes 'bar' (I've seen this before).
'egg' going within 'bar' is 'BEGGAR'.
(Other definitions for beggar that I've seen before include "He can't be a chooser, proverbially" , "Pauper or supplicant" , "Tramp" , "Pauper who seeks alms" , "One with no choice?" .)