It depends, I think, on how formal your service is going to be. In formal dining the charger would be removed after the soup and appetizers, but a less formal meal may not have those, so the charger would remain. There are all sorts of things one does in a less formal situation that would never be done in a formal one (place mats, paper napkins, etc.) so I think this would fall into the same category.
If this is a more informal family occasion, I don't think there is anything wrong with using something just because it looks good...it makes it "feel" more formal and can protect the tablecloth...both good things.