Some people - indeed, even some medical practitioners - say that EVERYONE should drink water only if it has a pinch of salt added. I can't stand plain water, I have a hard time getting it down. But with a pinch of salt, it makes me feel good, like I am doing something good for my body. Just saying.
Obviously, if you have been eating a good sized dish of v. salty food, such as salted fish, then when you get thirsty, you don't have to add salt to the water you drink.