Seems like you're a believer in the trickle-down economic model? Unfortunately in most cases it will be moved to a tax haven where it joins a big pile of money that will simply never be spent on anything but the incidental super yacht or a luxury mansion on a private island. Even the government can spend the money more effectively than that.
There are exceptions of course, but we shouldn't be dependent on voluntary acts of philanthropy to get the money invested back into the country that it was already owed to in the form of tax in the first place.
It's the difference between somebody putting their money into a savings account and putting their money into a mattress. The money in the savings account is still being invested into the economy, the money in the mattress is functionally gone.
And you're wrong that it's as "good as gone." It's not. It's just to be spent by someone else.