I think there's a middle ground in there somewhere. Many people experience "pain" and "lack" in other areas of their lives, and are looking to travel/vacation as an escape from that. Tying happiness and joy to "less" is just as arbitrary as tying it to "more". It's all about where you start.

I don't mean to be disrespectful but I really don't understand this. Why not just live in your car in the US? What's the point of going all the way to Asia just to live like a homeless person?

Myself, I've had enough pain in my life already (domestic violence and abuse) so I'm ready to spend my vacation in pleasure.

I traveled all around US by car camping, it was quite joyful. But it's not as social as being in developing world and getting to know unique cultures in natural ways.