Hi,
All protein on Earth begins in the Nitrogen chains in PLANTS - not in animals. There is zero reason or need to eat animals to acquire protein - there are many ways to acquire sufficient plants from protein only. Please do more research on the topic.
"They steer clear from such a job because their food components do not contain their requirement that could make them stand in such jobs."
Uh, no. It is true that, for example, in India - the Jains are the most economically successful sub-group and they are either vegan or almost vegan. They don't do the hard jobs because they have more money and pay non vegans to work hard. However, there are many international champion athletes that are vegan which dispell the myth that vegans are weak.