If you watched the show Tony had this weird intuition thing, Tony knew he should've killed Paulie at that point, all of Tony's issues with NY then pointed to Paulie laying down with NY pillow talking allowing them to put his life in jeopardy, also inhibited his ability to feed his family as NY taxed them for dipping on the low......Tony being oblivious to his intuition here may have got him popped in the last episode.....Paulie was a whole bytch for no reason the last season and the clear antagonist within his camp in the last season....Passed up time and time again.....Stepping on tony feet and such...him becoming buddy buddy with Patsy
Even early in them seasons in his funhouse episode,Sil warned him his true enemy has yet to reveal himself and then he killed paulie in that dream