Previous Harvey's Customers continue to come back to Harvey's with old chips and if they meet a sympathetic cage supervisor they will let the chips be cashed in but they don't have to.
The "Ganef" you speak of is just another chip collector looking for a few traders and a story to tell. You're just the other side of the story.
I would check Harvey's about twice a week when I lived at the lake, found some nice chips! Want to buy one or two? Check the latest chip rack for current pricing.

Sincerely, Steve Soden