I suggest that only 'some' (a few) people like to pronounce 'id est'. I almost never hear anyone say the words. Practically everyone that I've encountered or observed will pronounce just the letters 'i.e.'.
I'll go farther than that. It would be very difficult indeed to find an average college-educated speaker more than 2 years out of university who either remembers or knows what i.e. – or e.g.– stands for.