If they followed international law, they are required to settle in the next available country that is not at war. I agree that's partly down to the UK having a hand in the wars they are fleeing, but I see a lot of reports of illegals committing crimes and using ECHR article 8 to manipulate the system.
I stay at my gf's house for several days when visiting. They have never had to do a TM30. There are no snitches in her village. Just be careful who you can trust
I always hire a car when I visit my gf in Issan. I carry my Uk licence and an IDP but I have never been stopped, so I don't have any experience of what many posters are saying, but it makes sense to abide by Thai laws just incase