No, it is the countries 'surrounding' Thailand, 747.
I don't think anyone worries at all about the number of Tourist Visas issued from a 'home' country. That is the reason for a Tourist visa, for use on holiday, usually with a significant gap in-between each as the user returns home.
The, not unreasonable, aim is to try & stop people spending long term continuous periods of time in Thailand as 'Tourists'. I think that the authorities still fear that many of these people are actually working 'under the radar'.
It does make it difficult for people who are under 50, not married to a Thai national but are capable of supporting themselves without the need to work. However I do not think the authorities worry to much about that.
The immediate solution of the guy(s) I met this morning is that they will just go to Cambodia, as the Immigration requirements there for long term stay are almost non existent. I gathered that they may then return to Thailand some time in the future, depending on what develops...