Read about the Thailand-Israel Employment Cooperation (TIC). They are treated very well, and some make even more money than the local Israelis who work at factories for minimum wage. Thai farmers agree by themself to work OT, no one is forcing them.
I am also speaking from an experience as someone who lived in Israel with my Thai wife; we visited some places where they work because in some places where they work, there are also Thai stores nearby, and my wife used to buy Thai products there.
I spoke with a random Thai farmer regarding his salary, and he said it is around 80k-120k baht a month.
They also get discounts from the Thai stores over there.
As for healthcare, there is healthcare that employer provides access to, it's required by law.