As per Sammobile, the Galaxy S10 will have a pre-applied screen protector. This is because Samsung knows that most of the protectors will not support the ultrasonic fingerprint scanner. Due to which Samsung will give a screen protector pre-applied to the device.
However, expect none on Galaxy S10e since it got no ultrasonic fingerprint scanner. Since it been a plastic protector, pretty soon you will find several scratches on the screen. If you want to get good protection for devices like Galaxy S10 Plus, get a premium protector from Samsung. It will cost you around $30.
Since the time of Galaxy Note 8, Samsung is giving away free goodies. In the case of Note 8, it was the protective case.