What is a word for a person who throws a "fake smile"?

Most people, especially receptionists and air hostesses have the ability to smile in a fake way. Being professional, their smile isn't real. Inside they cry and die a thousand dead of tensions but they smile like a fresh mango. Well, I appreciate this for their job.

I wanna know what such a person is called who smiles fake?

Solution 1:

I would call such smile a Pan Am smile.

The Pan Am smile, aka the 'Botox smile," is the name given to a fake smile, in which only the zygomatic major muscle is voluntarily contracted to show politeness. It is named after the airline Pan American World Airways which went out of business in 1991, whose flight attendants would always flash every jet setter the same perfunctory smile.

As for the person, hospitality professional sounds like what fits best your description.

Solution 2:

I would call that a forced smile, though there's some implication that it could be easily detected as such.

Probably the best term is the one you used ("fake smile") if you want to imply that their acting skills are good.