It's not because they're AV actresses that they can squirt! They love sex, are very, very sensitive, and know their erogenous zones very well, which is why they can squirt in huge quantities! That's why they don't squirt even if they imitate what they see in AVs by fingering or thrusting violently. Squirting is proof of vaginal orgasm! It's the liberating ecstasy that can only be experienced when you reach the highest level of climax! Maybe that's why they're AV actresses.