Good point and usually car seats have to be factory sealed in the original box. Check with the airline but this is often the case. This means that a pregnant woman transporting a car seat for a not-yet-born baby, or a friend/relative bringing one to a child at the destination. Not very practical if it's a car seat used by a kid with the parent.

Some passengers have had luck with compensation after gate-checked items were damaged. There's probably insurance for it but I haven't looked into it myself. A few of you, especially those with high ff status' have had luck getting the airline to at least somewhat compensate for damage but this is usually on a case-by-case basis.