My 22-day inpatient stay was also 12-step based. We had optional AA meetings every night, and mandatory AA meetings once per week (Sunday nights). The meetings were all held at the facility (it was also a medical center/university hospital). There were lots of attendees from "outside" and we were encouraged to participate. I remember acting as a "greeter" a few times and being happy to do it because there wasn't much else to do at rehab in the evenings.
There were good things and bad things about being force-fed AA in treatment. On the one hand, I didn't feel like it was a great fit, and didn't identify with the prayers, etc. On the other hand, I was in rehab and if there's one thing I needed, it was a little discipline and structure. In the end I accepted AA was just part of the combo-meal and while I wasn't a huge fan, it did me good.
All that said, it would have been great to be presented with alternative options instead of AA every night. If they said "you must go to a meeting but you can pick which one", I would have shopped around more. Of course, a rehab center forms cliques and groups really quickly, and I can easily see how everyone would just follow the "cool kids" if they gave us a lot of options. Also, AA provided speakers that were available every night. I'd imagine it would be difficult for other programs to match that availability, and those who coordinated such events would have their hands full. Why book non-AA speakers if only 1 or 2 people are going to show?
In the end, sometimes people who've lost their way (ie those in rehab) don't need a huge sampling of options. They need to be told that breakfast is at 6am, lunch is at noon, AA meetings are at 6pm, and lights out are at 9pm. If you don't like it, too bad. The world doesn't revolve around your schedule, your wants, your cravings, and your problems. Alcoholics need to hear that and start living that way, especially in the early goings.