Actually, I've seen these targets get used both ways. I've attended training in a live fire shoot house and we were given multiple scenarios, including a home invasion scenario where the residents are home and had called 911. We were to go in there and confront the "bad guys" and rescue the residents. And yes, there was a target there that looked like one of these. It was a woman pointing a gun at you with a young child in front of her. It was only after we gave the "order" for the woman to drop the gun did the intructor tells us that she had "complied" and was the resident per the scenario. We covered for them as one of us "escorted" the residents safely out of the house. Then we went on to secure the rest of the house. The scenario ended with no shots fired as it turned out that the "female resident" had already scared off the intruders.
In the very last scenario, we were to respond to a shooting call at a house where the 911 caller had said that his son was shooting family members before the line went dead. We go into the house to confront this "son" and rescue any victims. We entered the house and found two mannequins on the floor with apparent gun shot wounds. We entered a room and found a mannequin of a young boy pointing a handgun at a woman mannequin sitting on a bed holding a baby mannequin. We hesitated and gave several orders for the "son" to drop his gun, but the instructor did not say anything. After a few seconds of our attempts to talk down the "son", the instructor yelled "bang, bang, bang" signalling that the "son" had began firing. Afterwards, the instructor told us that he was able to yell bang twice before we engaged the "son", and that at that point blank range, the mon and baby sister were undoubtedly hit by the son. In that scenario, the "son" was not to be talked down which we tried to do. It was a normal reaction for anyone to do. But this scenario was set up to be a lose-lose situation for us. We lost because we failed to rescue the victims by trying to save the "son", and we also lost as we failed to save the "son". We were left to think about all the "what ifs" and all the "damn if you do and damn if you don't" scenarios. It was a very sobering reminder of that split second decision we as cops may have to face.
Does that last scenario sound too far fetch to be true? The thought of it is mind-boggling and disturbing, but it does happen. I have a young son that I teach how to shoot, and my boy's got very good aim. As a father like many of us, I teach my boy what's right from wrong, and I know that this scenario will never happen to me. But as cop, training like these is valuable in helping me survive. You are correct that this is not Vietnam in 1968, but there is violence out there. Just look at the posting here
viewtopic.php?f=55&t=9397&start=300&st=0&sk=t&sd=a&hilit=4th+precinct for common calls to just one part of Minneapolis.