that would make since. However in Khon Kaen when I needed the letter for my bank account and my license, they required the 90 report which was quite easy. So I think as usual it all depends on which office you are going through. After all this is Thailand and there are no absolutes.
Best to apply for a Thai Visa online before you go. It's an electronic VISA, so you don't need to go to the consulate. I believe you can get a 90 VISA, and then get it extended in Thailand.