[munchlax]

Perhaps because they is plural. Plural is reserved for the royal family in some cultures.

[timemct]

'They' is also used when gender is unknown and has been for a long, long time.

Person_1: I found this great blogger whose writing I think you'd love.

Person_2: Oh, really?! What do they write about?

[munchlax]

Only in English.

[IAmBroom]

It's an English fucking word.