Dead people are distinctly immune to prosecution, and generally granted fewer rights.
Explosives and bulldozers are likely to harm whatever was motivating the entry in the first place. The vault system can be engineered to ensure this conclusion, as well.
And, sure, if enough perfectly engineered vaults were impeding the government from carrying out the activities it wants to carry out, there would be calls to make building/using such a vault illegal too. In the real world, such vaults, if they exist at all, don't meaningfully get in the way. Thus there is no reason to think about it. We don't create laws on what theoretically might be a problem in some magical imagined world. We only create laws after something is identified as an actual problem.
After your five ninja edits, it's been hard to keep up:
Glass relocker mechanisms have existed (in reality) on safe doors for decades and will often result in the destruction of contents if triggered and opening is still required.
Governments are normally seeking evidence: a stack of cash or a quantity of bulk substances are substantially harder to rig to destroy (obviating evidence gathering) than documents or data.
