You pay a premium for that high value declaration which means what you are really paying is a premium to have your package not kicked. This is like the airlines who have unbundled seat size and the right to bring a carry-on.
The takeway is that, anecdotally, the UPS $1,000 threshold appears to genuinely change behavior; anything less is pragmatically just another package subject to careless/willful transport abuse.
I don't want to pay an extra $10 for every shipment.