Everyone treats gambling the same way, that is to gamble for fun and also make money in the process. But there are some gamblers who think that they can survive only by playing gambling, which is a wrong prospective. In order for you to survive, you need a more consistent source of income and you just cannot depend on gambling which is only luck based.
I have to disagree with your first statement. Not all gamblers think of gambling or consider it an entertainment activity and gamble for fun. I know so many people who got attracted to gambling solely because they believe casinos are money making machines and that they can become rich overnight.
People should stop considering gambling as a steady source of income simply because all games are designed to make you lose on the long run.