This is an issue that boils under the surface of everyday Thai politics and policy making, pops up once a while with a scandal such as the one above and eventually gets eclisped by other issues while its problems remains mostly unsolved.
A good brief about the problem is found here, it starts...
"Since 1973, Thai workers have migrated to Middle Eastern countries such as Saudi Arabia, Iraq, Kuwait, United Arab Emirates, Bahrain and Qatar. Saudi Arabia was once the largest labor market for Thai workers. In 1990, following a diplomatic break between the two countries, there was a sudden reduction in the demand for Thai labor. Thai migrant workers had to turn to the job markets in Southeast Asia (Singapore, Malaysia, Brunei) and East Asia (Japan, Taiwan, South Korea and Hong Kong). As of 1995, an estimated 627,815 documented and undocumented Thai migrant workers were scattered around the world."
Source: A White Paper from pacific.net
The first labor policy was initiated in 1932.
Sample of a "labor campagin" here)
Migrant labor policy is pretty closely related to Thai politics. (What a remarkable synchronicity that the BKK Post makes the above report at the dawn of this government.) It was part of a campaign introduced in the 70s by some power dealers, gained bureacratic support and henceforth grew. It was at the same time partly, an emergence from the periphery, as cash strapped Isaan workers tried whatever they could to find a living. This was easy money for them but it has put them in cycles of debt-ridden woe and loss of property rights. Even if a new Ministry of Labor has been set up in 1993, the issue has been eclipsed by other more politically volatile issues of the increasing import of poorer migrant workers into Thailand. So the poor people from the Thai countryside are still more or less left on their own wits to deal with the sharks and snakes of labor agents in their hopes of hitting the jackpot.
There's an interesting description here, where it gives an explaination about how migrant workers or "tourist consumers" are tied to "traditional forms of Buddhist ceremonial" where
"More than just a welcome respite from the drudgery and discipline of factory jobs, these excursions allow labor migrants to make important claims about their experiences as members of the Thai nation-state. As tourist-consumers, migrant workers appropriate powerful signs and symbols of modern Thai identity and status; in so doing they contest (and at least partly rework) their material and ideological marginalization within contemporary Thai society."
Lastly, a succinct blog post by David Frazier from Taiwan, in "Pots: "Thai Labor: Widgets or Workers"