@Ian *******
When they want ONLY tourists spending a lot they indeed should close cheap hotels.
But nobody is saying there is no room for other tourists.
Thailand like all countries like to know who visits them and wanyt to know some background.
That is the reason visas excist, the longer people want to stay, the more you like to know about them.
For security of a country visa exempt just is a risk, therefore you want to grant that only to people spending a short holiday, because of lower risk, higher spending and more likely not want to buy a visa for a short time.
People staying for one or two months can of course also be high quality tourists, but in that case they would not have a problem to prepare their journey and apply for a visa.
You don't need statistics at all to understand that most people spending their holiday stay less than 4 weeks.
In most countries they don't have more days off from work.