[jackblack73]

[ QUOTE ]
As if he stole $1000.

If she loses her job as a result of giving out incorrect cash, that's her problem, not OP's friend. Whilst it is a 'moral' and 'upstanding' thing to return the money, doing the opposite is not stealing.

[/ QUOTE ]
[] Legal scholar

At least in Nevada, it's stealing.

NRS 205.0832 Actions which constitute theft.
(d) Comes into control of lost, mislaid or misdelivered property of another person under circumstances providing means of inquiry as to the true owner and appropriates that property to his own use or that of another person without reasonable efforts to notify the true owner.

I'm sure most states have a similar statute.