I have had hotels check for the entry/exit stamps.
I have had hotels that don't bother to look at the passport.
I think between your experience and mine, that about covers the Thailand hotels and farang passports debate, no?
WRT the OP, maybe the hotel manager or owner is the only one inputting passport info to the immigration database. If they're not around, the receptionist may be only permitted to 'collect' the info via the photo and share that with the manager or owner. Quicker than filling in a card and all that old-fashioned nonsense.