Why do they check the IC at budget hotels?
 

Hi guys. New here and need some advice from the seasoned and experienced bros here, if you don't mind helping :) What is the reason that budget or transit hotels would check the IC or passport? To determine age?

For example, if I bring a Vietnamese FL to a budget hotel, and she is of legal age, then is there any way that I could be convicted of a crime? Is it illegal to engage in paid sex with a foreigner on a social visit pass here?