Does a tourist on a 30-day visa need to register his address in Thailand?

Filling out a TM.6 Arrival card when you enter the country does not mean you don't have to notify immigrations within 24 hours by turning in a TM.30 form at the offices that require one. :/

@Ed***

, if they are in Bangkok they don't need to do anything because the immigration office in Bangkok doesn't care about the TM.30 forms at all.

If they're in an area served by another immigration office they might.

Thai Immigration act: Every foreigner should report the address within 24 hours, there is no limit on how long he stays at one address. Some Immigration offices are enforcing it, if you visit them for Extension of Stay. No report means a 1.600 Tb fine as many times reported. Other Immigration offices do not care at all. If he just stays the 30 days and than leaves Thailand, not much to worry about.