I wouldnt necessarily say that people in SD are better brought up but it sounds like you ran into some of the local trash in Fishtown. You would find the same in Kensington (Philly Kensington not SD). Its a tough working class town and some neighborhoods are not where you would want to be during the day let alone at night.

With that said Philly is a great town. Society Hill, Rittenhouse Square, Olde City among others are great. Surrounding towns and suburbs also have much to offer. Its just those hard core lower class ethnic neighborhoods you need to be careful in.