I'm thinking that trans-genders, being human, are probably fairly evenly distributed around the world. What happens after that is a mix of upbringing and the environment.(accepting/non-accepting). In environments where its more accepted, (for whatever reasons) you will probably find more.
Its a shame to hear that one of the prime motivations, at least in Thailand is money. I think Thailand and places like the Phillipines, etc., have been pleasure destinations for many, many years,(if not centuries),
for the worlds military, businessmen, and sexual adventurers. Lots of prostitution of all kinds.
So at least in Thailand, the motivation seems to be more about money, tourism and survival, than honest acceptance.
Such a shame. It seems to me that trans genders have always been part of the human spectrum of sexuality, and as such, will always be with us. Some ancient (and even some contemporary) cultures had a distinct niche or place for transgenders. At least mtf. The American Indian culture comes to mind, where they were revered, respected or at the very least accepted as a part of the group.
That being said, maybe(?) the world will become more accepting again as transexualism is slowly mainstreamed into the culture. (via the internet, television, etc.), and people realize that its a normal part of the human condition and come to appreciate their unique contribution to society.
Just look at the U.S. Ten or fifteen years ago, there were a few tgirls on a little thing called the internet, or you could go to a club if you lived in a big city, or find some in a few adult magazines. Now they are appearing in bigger numbers all the time; the internet has exploded with them, and you can find real tgirls all over the world. I think they have always been there, but now are starting to feel more open, more accepted, and they are coming out.
Not to say that its an easy thing-I know its not. But its easier now than in, say the 1950's.
To me, it just adds spice to life, and who dosn't like a little spice now and then?