I can't speak for other locations - or current (aka 2007) trends, but back in the day... I remember the local english-speaking group sharing the territory & kingdom hall - with a spanish-speaking group.
It was an interesting concept. We had territory maps that got checked out - and worked - door-knocking. Them? I don't think they knew what a map was. They were supposed to 'survey' the territory - going door-to-door, and locating all of the spanish speaking individuals, and giving us a 'list' of those - which we would 'skip' when we went door-knocking.
Well - we never got that list. So, we went to all the doors. On occassion, we would get the irate person at the door "You were just here!". That was a signal for us to back off, and see if someone else was in the neighborhood. We would usually see a group of spanish folks making their way down the street. If we approached them, they would get real nervous, clam up - and leave very quickly.
If they spotted us first - they would evaporate - without a trace.
Definitely not 'rule' followers.
Whenever I would mention (exasperatedly) to a higher-up about the foul-up, they would just try to change the subject. I don't think that the elders thought too much of the local spanish group, either.
Regards,
Jim TX