[Psalm 73]

"Police said if those who found the cash fail to come forward in a reasonable amount of time, they could be charged with theft."

I think that would be a stretch - unless the money was still in official bags when it was found, how woud anyone know it was from the truck?
I pulled in for gas one time and found about 25 bucks (ones and fives) scattered on the ground near the pump, with nobody around - was I supposed to bring it to the police in case the owner claimed it?

[rightwingintelligentsia]

Depends on the statutes of your particular locality, but technically, yes.

[Navy Patriot]

Actually, yes, in most states, found money is still the property of the person who lost it.

Usually you are required to turn it in to the police, and if unclaimed, it becomes yours after a period set by law, usually 90 days.

If you believe the found object has no value, you may dispose of it as trash, but, of course you may not spend it, that would confirm value, and hook you for theft.