Cinemark said its Movie Club subscription program has passed 500,000 active members, more than double the level the exhibitor had initially projected.

Rival exhibitor AMC announced it had reached the 500,000 plateau in November with its Stubs A-List service. Both major circuits are benefiting from the instability of MoviePass in recent months. While it blazed a trail and popularized subscription moviegoing in the U.S., MoviePass has whipsawed customers with app outages and several pricing and policy changes as it seeks to stay afloat.

For exhibitors, subscriptions are seen as a way to cement customer loyalty, which can boost all-important concession revenue and provide valuable data.

Movie Club subscribers tend to go to Cinemark theaters more often, the company said. Since the program’s launch last December, Movie Club members have bought 10 million tickets, and accounted for 8% of Cinemark’s third-quarter domestic box office revenue.

“The popularity of Movie Club continues to grow as more of our moviegoers recognize the value that our program provides,” said Cinemark CEO Mark Zoradi. “Features like our new gifting program have driven member acquisition and unique member benefits such as rollover tickets have driven member retention and helped us reach this impressive milestone.”

Movie Club’s pricing strategy differs from some rival plans. For $9 per month, the Movie Club members get one ticket to any 2D showtime, plus discounts on extra tickets and concessions and free online reservations. Unused tickets can be rolled over month to month and never expire for active members.