This works both ways. Both parties should at least start with a smile.
Reminds me of a lad arriving at my hotel in one Thai town away from the usual gay destinations. He was carrying more weight than I expected and looking particularly miserable. Most lads manage a smile, which I appreciate might not be the easiest thing when meeting someone over twice their age.
However, despite 2 reminders, my miserable visitor still forgot to bring his ID card and therefore I had to send him away. He contacted me about an hour later, but I declined.