I have cut down the amount of salt I use in cooking and no one adds extra at the table except my mother in law. She covered the whole plate of Christmas dinner in salt without even tasting it while she was waiting for me to find some from the kitchen.
A lot of the ingredients that I use in food preparation already has salt in, like stock cubes, mayonnaise, butter and margarine, cheese, pesto, even bread, so I don't add anymore salt.
I have done it gradually over the years so we have all adjusted our tastes.
Though I did put quite a bit in to my homemade stuffing at Christmas even though there was already salt in the bacon and the breadcrumbs.
I think that if you don't get the seasoning right during cooking, you can't really rectify it at the table. Adding salt at the table to under seasoned food just makes it salty. Adding pepper would be preferable.