@John ********
where does it show that you must have a Thai bank account to obtain the LTR VISA ?
Make an application for the LTR VISA using the Thai Board of Investment website application.
Once Approved... then you meet the BOI staff in their Bangkok office and they do the final steps including walking you to the Thai Immigration office to have your LTR VISA STAMP placed in your passport.
********************************
Once it's approved then when you arrive into Thailand and have your LTR VISA placed in your passport