I'm in the same boat here, I don't quite understand the use of this? maybe in a situation like XPY where stakers 'accidentally' had the wrong rate and other such blunders, or possibly in the interest of controlling the supply?
It may be better to explain to those not familiar with these things exactly the use of destroying coins, instead of whether or not 1/2^128 matters? (which really, it doesnt with current computing powers, unless using a qc as stated above)