Because everything in Cambodia is 1/2 or even 1/3 of the price of Thailand's prices. Hotels, drinks, food, sex, taxis, whatever. And they are a lot friendlier to people who pay them for their services. For everything. Thailand is not what it was. Thailand had a coup d'etat in 2006 that removed the old government that was friendlier to tourists and foreigners. Most of the people I know from the SEA forums have left Thailand to go elsewhere. Some went to Vietnam, some went to the Philippines, some went to Cambodia. Some just went back home and said fuck it. But almost everyone is leaving Thailand. Long term visas are more expensive, girls are more expensive, everything is more expensive now.
You can pay a girl for the whole day to be your girlfriend in Cambodia for $30-60. In thailand you are looking at $90 or more. The prices are going to be all different after China virus is over. My guess is the prices will be lowered because I think less boomers will be travelling to SEA for sex. They'll still be afraid of catching some kind of weird slope bug, is my guess. So you could potentially profit off of this. I am trying to get myself healthy enough to go to Cambodia once per year. But my health is so seriously bad that its going to at least take me 2-3 years.