each bank, each branch, sometimes each member if staff can invent their own different requirements depending on which way the wind is blowing. Happened to me last week.
last time I asked my local.office about getting my yellow book they said bith that my disabled house owner must attend the office and I can nit get a yellow book without first marrying a Thai. Plus, this yellow book requirement for a bank acvount is not consistent, it is not a universal requirement. Having a yellow book and I'd card is an option, nit a requirement. Yes it makes life easier, but getting one is a different challenge depending on your local office or which staff you talk to.
i think there was no rule at the time they opened them, the decision was an after thought. And some who have non O and OA visas when they opened are being told their accounts are frozen or being closed, but without explanation of any reason, or any evidence for any cause for concern.
I opened mine on a visa exemption and the rules were clear at the time that it was permitted. Since changing to non immigrant O this is the 3rd time to sign and submit the same documentation required to prove my I'd, the banks choose not to give any reason, so I feel disinclined to believe any explanations off Facebook. I see cases of new OA visa holders who are now having their new accounts closed a few weeks after opening. No communication, no reason, no evidence of any wrong doing or rules being violated. Many millions of baht are leaving as a result.
some were, some were or, some on a OA or different. Some being hit, some not. Some contacted, some not. Some think they will never have a problem... and next, bam. Good luck.
asking for an explanation can just be met with silence. Trying to understand why many things are done like they are is something not even many Thai nationals or staff at some of the businesses and bodies say they understand. Even talking about it can make some angry that you should even have an opinion or ask a question, they seem to consider it some kind of threat against the general order. Some may say it is all designed to milk more from foreigners and make those in power gain more wealth, and keep those in poverty where they are. Critical thinking or questioning can be met with differing levels of intolerance, or worse, although not all responses are this way, some are quite understanding and as confused as the rest of us.
The requirements for some visas is to deposit a specific amount in a Thai account for a specific time. Yet now, many are having problems any acvount without having a long term visa. Have you heard of the book Catch 22? Same, same but different.