I'd agree with you that being in public in anyway is how most people get caught, however they are advertising the fact that they are working in Thailand on the

I'd agree with you that being in public in anyway is how most people get caught, however they are advertising the fact that they are working in Thailand on the internet. More importantly though, they are responsible for their attendees and should consult lawyers or immigration as to whether it is legal or not. Having consulted immigration previously myself I firmly believe what they plan to do is illegal.