What's the point of security doors?

Seriously, am I missing something? Anomaly basically says "you need these doors to keep your entities in their cells". But the second an entity manages to cast off its chains, it just... opens the door and leaves.

This was already kind of bullsh*t with magically-key-stealing-prisoners, but it's doubly bullsh*t that apparently this alien horror can just waltz out of the specifically built security door. Why even have them, then? Might as well just put a normal door in if it's apparently all the same to the monster.