Would stealing gold harm the economy?

It would have to be a very small economy indeed. The impact on inflation would be minuscule.

Hey! You're not old enough to drink! Now go and die for your country!!!

Actually the economy is movement of money. So you can think of it like this:

Let's say a guy has $1 million which he is going to buy a house with. After he bought the house, the person who received the money was going to buy some new trucks to expand their business. Also, the truck salesman was going to pay salaries and order more trucks manufactured, etc. You can see the money will be moving around the economy, causing it to grow.

What happens if you steal the $1 million and burn it up? It will never move again - the guy won't buy the house, the house owner won't buy a truck, etc. So you have slowed the growth of the economy.

But what happens in this movie? There's a bunch of gold in the safe just sitting there. It was not being spent, it was not growing the economy. Now you steal the gold, and it's still sitting there. There's no impact on the economy. Actually if they start spending it, it will have a positive impact on the economy compared to the original owner who didn't spend it.

Someone correct me if I'm wrong, but unlike burning paper money, the gold is still physically there and still worth the exact same amount so the impact on the macro economy is 0, but the impact on the individual's economy is massive (positive for the thieves and negative for the original owner).