How would ANYONE benefit?

He'd be dead.
We'd have done something wrong.
Our children would have seen us do something bad and think its okay to kill, instead of seeing us be revolted by the idea.
I suppose Albert Pierrepoint's successor would have made a few quid, but they usually need people down at Tesco to collect the trollies - he could do that instead.

Think Ake! As my Uncle Harold from St Helens, used to say, 'Think on'.