Targets like that are designed soley to remove hesitation from the shooter. If they shoot at the targets enough, they will be trained to shoot the real thing without hesitation.
It's conditioning. That's what the military is all about. Especially for troops that actually are going to shoot guns at people, military training is designed with the goal of training the soilder to kill his enemy. They used to just shoot at outline targets, then pictures of "Terrorists" now it's Americans with guns.
While I'm not sure of the viewpoint of the following site, it does link to a lot of established news organizations and videos of Military training in US cities.
http://gulagbound.com/37220/list-of-many-military-exercises-on-u-s-cities-collectivist-context/
Something is going on, what we won't know until it happens. Is the US Government prepping to invade our cities? Are they training for possible intervention in Syria? Why does DHS need 1.6 Billion rounds of ammo? To put it into context, that's 24 years worth of ammo if it is used at the rate it was used at the height of the Iraq war.