@Doug *******
Eight years ago I walked into a Kasikorn branch, Phra Khanong, Bangkok, on my first day in Thailand with my Thai girlfriend. I had a new OA visa in my passport. I opened a bank account with no problems. My girlfriend told them to use her address.
Last October I opened a bank account in Bangkok Bank in Sisaket province. This time I had a yellow book and an LTR visa. I opened an account with no problems.
It seems to be much more difficult for newly arrived expats these days.