Is this correct that I google it
Airline Enforcement: While Thai immigration officers inspect tickets selectively on arrival, departure check-in staff for airlines strictly enforce this requirement and may deny boarding if you lack proof of onward travel. Airlines generally prefer confirmed flight bookings over land transport, as land tickets can be harder for them to verify.
..................................................
Thai Embassy in England:
Foreigners entering Thailand by any means under the Visa Exemption scheme are required at the port of entry to have proof of planned travel (confirmed air, train, bus, or boat tickets) to leave Thailand within 60 days of the arrival date.” �
Thai Embassy London