Physicals locks are poor analogies for encryption. A physical lock isn't designed to provide robust security - it's trivially easy to open almost any lock - it

Physicals locks are poor analogies for encryption. A physical lock isn't designed to provide robust security - it's trivially easy to open almost any lock - it's to make opening it a noisy, slow, dangerous and expensive affair. And even if you have that magical perfect physical lock, few houses (or other containers) are impregnable. A physical lock is more like an effective intrusion detection system - it's not going to prevent hacks, but it might make those that have something to lose think twice, and at least you're likely to know if you've been robbed. Just like intrusion detection, physical locks make it at least somewhat risky to even try to break in - after all, you might get caught.