Do my family members need a re-entry stamp if they fly back to Thailand the same day from Bali on a single-entry visa?

The user asks whether their family, visiting from Egypt with a single-entry visa, would require a re-entry stamp if they fly to Bali for a week and then return to Thailand on the same day to catch their flight back home to Cairo. Responses suggest that if they are briefly re-entering Thailand for transit purposes, a re-entry stamp is necessary.