Probably because the fuckin people who fuckin watch these fuckin movies like to fuckin see the fuckin woman's face because it's fuckin hot to see a fuckin woman in the fuckin throes of fuckin pleasure. Hope that fuckin helps.
Why do they just film the fuckin face of the girl all the fuckin time? 90% of the porn movies make this fuckin shit. The porn industry has a fuckin terrible camerawork conception.