He said stock. Salt is not needed, and there are plenty of decent ways to make a great vegetable stock without it.

That said, it's not clear why you'd regard adding a little salt as bad unless you had a serious medical condition prohibiting it. I get that you'd want to avoid the absurd amounts a lot of prepared foods include, just for taste.

I use unsalted stock exclusively in my cooking, because I like the ability to add salt in later, and if I'm adding other salty ingredients, I don't have to worry about overdoing it.