First, my country doesn't invite tourists at all.
Second, 1999baht per month it is not a "couple of quid", could be hundred soon, haha.
Third, how does the existing system prevent a wrongdoer come in ? If there is a working filter, let it be!
First, which is your country that does not have visitors at all?
Secondly, "a couple of quid", is an expression, a figure of speech. In the context of my response no one would reasonably interpret it to mean £2.
Thirdly, there is a working filter and part of it is not allowing people the privilege of buying a visa on demand. The visa application system does not allow 100% of applicants to enter, it only allows those who meet Thailand's requirements to enter.