Depriving them of the ability to work and be a productive citizen. Depriving them of their existing assets (fines), and as stated by Manning and others, that grand juries have tended in the past to victimize those they call as witnesses.
Unfair? Unnecessary? Unfitting of the wrong? Those are all things I don't know enough to really say or discuss in an educated manner.
Why would I assume you meant the colloquial "cruel" and not the legal "cruel" here? Perhaps you should edit to clarify if your intent was the former as opposed to the latter.
Perhaps you should also edit to clarify your intent.
This is the same line of reasoning Alex Jones uses to justify his conspiracies. "The government had Project Northwoods, why isn't [conspiracy] likely?!"