It is typical of Thailand that they haven't identified this market and have failed to supply sufficient orphans for the needs of foreigners. I personally find it very distressing that the parents of Thailand insist on looking after their children themselves rather than availing them for foreigners to drool over. After all if you travel half-way round the planet you'd think they least they could do would be to supply at least a handful of endearingly engaging little children....even handicapped would do...(not too much though).
However, I understand Tesco's will be opening a range of orphanages all around Thailand so that tourists will be able to indulge their sanctimonious and charitable urges.
Of course it had to be an English company - not a Thai one to realise this gap in the market.