Let me answer the question as follows - I am a pescatarian (i.e. I eat fish as well as veggies), and I have never, ever had an issue in QF J finding something to eat (a veggie or a fish option) on the standard options provided. But if you are a strict veggie, i.e. you don't eat fish, then you would be taking a significant risk not requesting a special meal.

That said, there are so many food options on the service - like the Express meal option, and the Refresment options, plus they always have salads - that I doubt very much you would go hungry.

You can see what I mean here (English bit on second page) - a sample QF J menu on a route to China: http://www.qantas.com.au/infodetail/...sinessMenu.pdf

BTW, some people do the following - order a veggie meal, but if they then see something on the regular menu they prefer they ask for that instead (in a polite 'could I possibly trouble you...' / 'might I be cheeky and request...' way, of course!). Assuming there are enough meals to go around this usually is not something the cabin crew have any issue with.
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