Based on the experiment:
When I hit the bottom coin of the stack, only the bottom coin had the great change of position. The other coins at the top of the bottom coin might have move a little after the bottom coin was hit, but after that, they stayed in the stack and it seem like they were not greatly affected by the hit in the bottom coin.
This is because, the other coins were able to resist the force exerted on the bottom coin and they were able to do it because of the coins' inertia. The other coins had the tendency to remain at rest. For the bottom coin's part, it was not able to resist the force exerted on it especially because of the physical contact.