In my opinion, there is NO justification for a prosecutor agreeing to a plea bargain with no jail time for a quarter million dollar theft. And even less justification for a judge either accepting that plea bargain or imposing such a sentence without the DA's approval.

Of course neither you or I know the details of the available evidence other than what has been reported. You would agree that the relative strentgh of the case has to be considered by a prosecutor in evaluating a plea deal. You also don't know what position the victim took in this regard. If the Victim(the Casino) tells the prosecutor that they don't want to see the defendant go to prison that also is a factor you would have to consider.

"our prisions are full of people convicted of stealing a small fraction of that amount or other similarly less serious crimes,"

Of course our prisons are full of people convicted of drug offenses which are much less serious offenses, but the prisons are filled primarily with repeat offenders.

Few people go to prison for their first conviction.