Why would a hotel manager in Jomtien check my UK passport's exit date?

A traveler mentioned a hotel manager in Jomtien checking their exit date on their UK passport, an event they had not encountered in 16 years of visiting Thailand. Comments suggest this may be a routine practice for hotels to ensure guests are not overstaying their visas, primarily for TM30 registration purposes. Others shared experiences and opinions on the increasing observance of immigration rules in Thailand by various sectors, especially since the digitization of immigration processes.