In one sense that's true, but as they say in the security field, the fact that someone could break down your home's front door with an axe doesn't keep us from

In one sense that's true, but as they say in the security field, the fact that someone could break down your home's front door with an axe doesn't keep us from locking our doors. Even if you generally trust your infrastructure provider, there's still no harm in considering the different layers at which you are and are not protected from certain attacks. For example, a single rogue employee might be able to do some harm in one area, but not another.