I was pretty much going to say what Cory said but then he already did.
Here's what I have to add though. I really can't see a way that a coin can be permanently stuck halfway through a bottle. If it is halfway through, then there's obviously a hole at the point of penetration. Since you say they can have the bottle, an illusion of the coin halfway through would be discovered with thorough inspection.
So how can it be permanent given such a case? More importantly, what's stopping you from just adding a little more push to get the coin through? The coin is largest across its center, or diameter, so if you manage to get that part through, surely the rest of the coin should be no problem. If it's halfway through, it's like you can slip the coin in and out.
Definitely work it into a routine. Pushing a coin halfway through a bottle, and yet leaving the bottle undamaged is what you're looking for. Proceed to push it in completely, move it around, etc. Maybe your original idea would work with objects other than coins and bottles.