Average expat household lives of 3-4,000 a month in
Thailand...
Avg 1.5m of which 800k border bounce x 4 which are accounted in the 20m tourists per year, expats (yes high turn over) + tourists that stay longer than 180 days (3%) + avg spending 120,000 THB x 12 months = x
That's the amount of money they are looking at loosing a chunk off.
UK Tax Treaty with Thailand for example ONLY covers State based pension (25ish k THB).
Avg villa rental in Phuket now is 30-40k.
UK doesn't charge tax for non-residents, so Thailand will charge tax for their private pensions coming in.
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Have to look deeper than the claims.
Then go into other things, medical, insurance for my kids is 100,000 THB per year, schooling (babies) is 30,000 THB per two months, and Swimming School is 16,000 THB per two months, these rise to 300,000 THB per term, and 60,000 THB per term.
There's entire industries created around education.
There's entire industries created around expats.
There's entire industries created around health care.
These services bring in huge amounts of revenues.
As a tourist you have no use for these services except perhaps healthcare (trip to A&E).
Then look at the marine industry, the reason the services side of that has exploded in demand is due to the expat ownership, instead of Langkawi (where Phuket is concerned).
Would you honestly pay 40k $ + 35% to have your mast sorted, rigging, etc done ? or would you send it to langkawi and have the people setup shop there (tax free imports).
That industry alone employs about 10,000 THAIS directly and indirectly and over 200 companies in Phuket alone.
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Real Estate, property rental prices have doubled in my area, purchase prices have trippled.
That's all tax at the rental side, and the transfer side.
All those funds (tax receipts would be gone).