It's kind of a continuation of what the previous operator did, but one local theater had baby nights. Not sure if they still do. They say babies under 1 are free, although they typically don't ask to see ID. The lights aren't quite as dim, and the audio is dialed down. And one rule is that you know what you signed up for, so no complaints about crying babies. This place also serves alcohol, so it's not unusual for a parent to be there with a beer in one hand while carrying a baby.
I don't know if one theater does it, but another one in Oakland, CA that's carrying on the tradition has it.
http://www.thenewparkway.com/?page_id=136
While the New Parkway Theater is an all ages theater, and you are welcome to bring your baby at any time, Baby Brigade is specifically set aside for parents with infants. Instead of having to get a babysitter for your baby in order to do adult things, why not just bring your baby to the movies? We’ll show one of our regular features each week, stroller parking and a dimly lit pacing area is available. The best part…an audience that understands if there are a few screams or whimpers along the way.
We have two Baby Brigade offerings on most weeks that should appear listed further down the page:
1) Saturdays (mid-day or early evening)
2) Thursdays (early evening)
Although we do lower the volume of the previews and movies please note that some of the movies are loud–or at least loud for baby ears–and we recommend bringing ear plugs if your baby is sensitive to loud sounds.