they have "connections" with some immigration offices>
Approval of conversion from visa exempt/tourist visa to non o & extension's is Always up to the immigration official
person Does NOT have to be there ( except Jomtien) afaik
example , out of the 22-30,000 some agents charge in phuket for extensions, no baht in Bank
1, 900 goes for the extension, 2-5,000 goes to the agent, remainder goes to .....