We just returned yesterday from a 7 night trip. I have to weigh in as we had several groups where 1 or 2 people would get in line and then about 7 to 10 family members would then join them (I counted). The last time this happened (on Indiana Jones), there were about 3 people (after several had already cut) saying "excuse me" and trying to pass. My sister said, "are you cutting in line?" to which one of them replied that she was sorry. I said," you're not sorry if you know what you're doing is wrong and are doing it anyway." The group left and many groups around us let us know that they were happy we called them out. This is the first time we have said anything, but after it happened several times, we were just over it.
That being said, we met many more nice, friendly guests than rude ones.