I have never, in the past 5 years flown into BKK withba return ticket. I always buy one-way. This was done first with a Non-O and then with an METV 60-Day, purchased for USD $200 in either NY or LA. Neither immigration nor ANA or Thai ever flinched.
And in the hospital's, and now Surat Thani's immigration office's opinion, it means precisely that. We are all entitled to opinions, but some actually matter.
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