Because it’s an out-of-reach luxury for a lot of people, and those few who have tasted it with success will recommend it.

As to whether you should consider it yourself: are your negative emotions heavily impacting your day-to-day functioning? Are the causes external, material, and outside of your control (I.e., stuck in poverty, or a bad country)?

If the answers are yes then no, then maybe consider it if you can afford it. But yes, human emotions are normal and varied as long as you’re able to reasonably and healthily cope with them.