I ever heard that people choose to quit their job for doing some crypto job. Whether it is trading, mining, or bounty. But I think that's the worst idea. Maybe they think that kind job like that can earn many profit but they doesn't looking at the risk and keep do it. Look at the market, they stay red and it will hard to get profit from investing or trading. GPU price is more expensive as well as a lot of capital to be spent when starting mining. Also Bounty Hunter has bad condition right now with too many SCAM ICO which caused some of them just wasted their time and doesn't earn anything.
How they can earn money for daily need if only depends on the crypto?
your statement is very true, I also do not agree with people who decide to focus on crypto and leave their jobs, even though the decision is actually their right.
the revenue generated from the crypto is unpredictable, so it will be difficult to balance our spending with income from crypto, so I also do not advise to leave the job and just focus on the crypto.