So what's the problem?
As long as they work, pay their taxes and contribute. If the official stats say immigration is a net benefit to the country, and we need immigration for vital work like doctors, carers, low paid labour etc, What's your issue?
Believe it or not, you see those big high rise buildings in Bangkok, they're built majority by labour from Myanmar. USA, Dubai, Australia all have high immigration numbers. Hell Thailand has let nearly 40 million tourists in this year.