Gee I’ve lived here for 20 years and never was told I need to register when I stayed anywhere in Thailand over 24 hours! Don’t turn me in! Hotels will always copy your passport that’s all is required.
Been here 20 years and have never worried about travel where I wanted, where I want, or when. I’ve never been ask to verify with Immigration. Yes the hotels will copy your passport, but don’t worry about it.