Yes, all that may be true but you clearly haven't thought it through from a Thai perspective. Indeed, the government could make more in tax revenue if it didn't support the home market but that would mean the home market producers wouldn't survive and the country would become reliant on wine imports. So, that would mean a loss of independence, local producers would go out of business plus imports would be higher each month and this would mean more reliance on goods exports to protect the balance of trade and the value of THB.