The point is that if you argue a soldier shouldn't have Target or Amazon on their phone, it's pointless, as they still have Safari or Chrome.

I'm not sure that's a complete argument.

If you're arguing that soldiers shouldn't do business with Target or Amazon on their mobile device, blocking an app won't get the job done, agreed.

But if the argument for blocking the app has to do with untrusted native code running on a device used for military purposes, the surface area of a browser is much smaller than the surface area of a plethora of native apps.