Well, it was partly affection. But it was also to show the damage in Frodo, and the need for healing, and the whole response in the Shire.
That is rooted, I think, in the reception that soldiers got when returning to WW1 England from the front. "Roger, Pip-Pip, Old Boy, good to see you back home. Have your old job back." All very well-meaning, but for a world-war soldier, sometimes quite impossible. They were irrevocably (sometimes irreparably)
changed.