While I have never considered entering roulette chips back into play, I have figured the math and it just isn't worth it. Lets say I harvest a stack of chips costing me 20 dollars. Now I buy into a game making the chips new value 10 or 25 dollars each. If I buy into the game for 100 dollars I would get 10 or 4 chips depending how I value them. Therefore you would need to spend a lot more to reintroduce a stack of 20.
So now you buy in for 500 dollars valuing your chips at 10 dollars each. You are not just going to buy in and cash out. You will have to play first. Odds are you will lose. Now you reintroduce your chips for an additional 200 dollars. By the time you cash out your profit (if any) wouldn't be worth the price of the penalty if caught.

Barry