What the purpose of the System.StartUpCopy included in all firemonkey project?

问题

When I create a new mobile app with Delphi, I have this dpr source:

program Project1;

uses
  System.StartUpCopy,
  FMX.Forms,
  Unit1 in 'Unit1.pas' {Form1};

{$R *.res}

begin
  Application.Initialize;
  Application.CreateForm(TForm1, Form1);
  Application.Run;
end.

I do not understand, what the purpose of the System.StartUpCopy in the use? With System.StartUpCopy.pas, on ios, it's look like the app will copy file from

/private/var/containers/Bundle/Application/2BE5407C-4DD9-5A08-110F-C12510C42BF3/myapp.app/StartUp/Documents/

to

/private/var/mobile/Containers/Data/Application/2BE5407C-4DD9-5A08-110F-C12510C42BF3/Documents/

but I don't fully understand why because now my app will use twice more disk space, and my app can access both directories so I do not understand why we need to duplicate the resources :(

来源：https://stackoverflow.com/questions/61942454/what-the-purpose-of-the-system-startupcopy-included-in-all-firemonkey-project