Many people believe that they can survive through gambling and make it their source main source of income, the truth is that gambling doesn't guarantee steady income because the outcome most times depend on luck and probability, casinos and betting platform design the games in way that it will favour the house in the long run, this shows that even if gamblers win today, they still have high chances of losing later, because of this, many people see gambling as entertainment, something that one can do for fun with the money one can afford to loss, and when one begin to depend on gambling to pay bills, feed family, or to survive, the pressure can make the person take more dangerous risks, chase losses, and end up losing more money.
NOTE: anyone that depend on gambling as their main source of income will face risk, depression, frustration and financial losses, there's no professional gamblers, just have deep knowledge and accept that losses are going to happen sometimes.
Gambling is just for entertainment and will always remain like that, those gamblers that feels they can make steady income from gambling are not truthful to themselves because wins does not come often.
It is only casinos owners we can say makes their livelihood from gambling as a business as a source of income, gamblers depends on luck to win their games, except those gamblers that consistently wins their games which is very rare.