Absolutely, getting a shower and having soap on your body is Magical Jesus Heaven when you've been in the dirt for a longer period of time, and it's definitely an important morale motivator, actually just longing for it, so it definitely has survival value apart from basic hygiene making sure to let the body heal and not catch infections and so on...

I suppose the scope of the situation matters for what we are talking about. In a true survival situation, it's an afterthought. In anything below that it becomes proportionally more accessible and pertinent, of course.

Edit: Shit I answered twice without noticing, I just re-read your comment and had something else to say I suppose :) <3