Think about it. 

* Less rewards for those who whore, as they get less exp for those kills.

* Could potentially lead to 'whack swaps' between cities, you kill this guy in my crew, I kill that guy in yours, and we both benefit more.  Would bring a whole new element to the game per inter-city relations, good and bad.

The way I see it, the difficulty of finding and targeting someone your familiar with, since they are working and known within your own city, is less than that of someone from somewhere else.   I would think this should relate to unsponsoreds as well.  If their home town is your home town then you have access to better information about them (as they work your own streets), someone who is from another city would be a tad more difficult to arrange the kill.

Discuss...