I'm suggesting it specifically because vegetarian soups tend to have less umami (the savory, "meaty"/MSG flavor). Non-veg cooks can just simmer bones, etc., but vegetarians need to get umami from mushrooms, grilled root vegetables, boiled parmesan reggiano rinds (which are totally awesome, BTW), miso, etc., and vegemite is another option.
It's quite cheap (if you buy it in "I'm going backpacking forever and may not make it back to Australia"-sized jars) and keeps forever (what's it going to do...become more salty?), so it's pretty convenient.
The only group I've seen seriously struggle with the whole "OMG I'm killing bacteria by breathing, what should I do" issue are the Jains, and I find them pretty silly. (I'm not a vegetarian, but when I was...I still found them pretty silly.)
Some vegetarians are amazing cooks, too. Constraints can really drive creativity.
It was all rather eye-rolling. I can definitely see Jains getting in on that nonsense.
I've found it useful time and time again to be wary of recent converts of all stripes, whether it's Veganism, Objectivism, Haskell, etc.
If I remember, enlightenment was not found in the extremes under Kaundinya.
That message really seems to be lost I think. Both in the purposeful following of an extreme ideal, or in not being mindful of extreme habits.
Even if one is not a Buddhist, the concept of the middle path can be wonderfully freeing from expectations of extreme ideologies that sometimes ferment under civilizations.
The popular American impression of Buddhism is pretty weird - historically, it's heavily skewed towards Japanese Zen Buddhism, but secondhand, from the Beats* . The way people talk about Zen, you'd think it had antioxidants or something.
* Due to their infatuation with the San Francisco Zen Center, Shunryu Suzuki, etc.
But can vegetarians eat bacteria? They are animals too.