You're absolutely right that these tactics aren't acceptable in a typical firefight. But these men aren't there to engage in a firefight. They're there to get civilians out of the way and to safety.
By stepping out from cover and drawing enemy fire, they're giving the guy who's running to grab that child some breathing space. Simply laying down suppressive fire isn't going to work here: there are only two of them, and there are a hell of a lot more hostiles just by the sound of it. They need to give the enemy a more inviting target.
So when they step out, they aren't doing it because they want to be badasses or because they're idiots. They're doing it so the enemy is less likely to fire in the guy who's about to have a kid in his arms.