Just to tamp down on the hyperbole a little, while Burmese legal refugees and illegal immigrants are mercilessly exploited, slavery (and polygamy for that matter) are illegal in Thailand, and many Western people who think that their money insulates them from the legal system find out the hard way that no, it does not.
This was 13 years ago, so the political situation may have changed. But this guy was very much operating in the open, and definitely breaking all kinds of laws. He’d been doing it for more than a decade, and no jail time yet.
He did also finance construction of an elementary school and some other community improvement stuff. He didn’t explicitly talk about bribes, but I’m sure he was paying people off. At least at the time he seemed to have figured out a way to avoid the law. But maybe corruption is down and it finally caught up with him - I’m definitely out of date here.
It was one of the saddest and strangest experiences of my life.
But yes. People do this. It is weirder than you think.