From what my teacher would say, they have been socialized to like to accept the concepts of Scientology. Someone or something came into their life, whom or what they liked, and accepted the ideologies that these things or people gave to them.

Scientology's founder, L. Ron Hubbard, actively encouraged enlisting celebrities into his church. Hubbard is said to have recognized the importance of artists to society -- it is no accident that Scientology then has such a strong presence in the Los Angeles area. "Scientology has had a written program governing celebrity recruitment since at least 1955, when L. Ron Hubbard created "Project Celebrity", offering rewards to Scientologists who recruited targetted celebrities. A Scientology policy letter of 1976 states that "rehabilitation of celebrities who are just beyond or just approaching their prime" enables the "rapid dissemination" of Scientology. "Scientology policy governs the Celebrity Centre (the main one in Los Angeles and others in Paris, Nashville, and elsewhere), stating that "one of the major purposes of the Celebrity Centre and its staff is to expand the number of celebrities in Scientology." (Scientology Flag Order 2310) Another order describes Celebrity Centre's Public Clearing Division and its goal, "broad public into Scientology from celebrity dissemination"; this division has departments for planning celebrity events and routing the general public onto Scientology services as a result of celebrity involvement."

In addition to what fredhetz said... The Church of Scientology runs a few schools and workshops for actors and artists - the largest one being the Beverly Hills Playhouse which is headed by Milton Katselas. Actors from beginners to veterans to celebrities attend classes or hold workshops there. Aside from developing the craft, they integrate a lot of Scientology philosophy (business/life management). I was a student there and actually found a lot of it very interesting and useful in daily life. But on the religious/spiritual side, it was a bit scary. People came and spoke to you with eyes that stared through and past you... like you were being drilled through the forehead... But that's just my experience...

When compared to the entire population, I think the percentage is pretty low. It's also not something we know that they will really stick with or if it is merely a fad for them. After all, it DOES give them good press and exposure, positive or not.

Cause actors are the typical easy prey, they have cash and they typically don't want to pay tax. I dare say they are reaping some tax deductions in some way. Good on em for finding the loop hole with in the loop hole.

Money, and publicity with a pinch of stupidity.