Well they actually literally didn't stop any men from entering. One did and they did nothing about it.
Ah okay, I see now that one man bought a ticket. (Though I don't see anything about him actually attending.)
I guess that makes their statement slightly more credible. Though the original advertisement seemed pretty clear they would be stopping men from entering:
"Apologies, gentlemen, but we're embracing our girl power and saying "No Guys Allowed" for several special shows at the Alamo Downtown Brooklyn. And we say "Women (and people who identify as women) only" we mean it.'"
Especially the last sentence, implies they would indeed discriminate and possibly bar the entrance of a male-identifying ticket holder.
Since discriminatory advertising caused discrimination in practice, even though one guy was brave enough to try, I'm guessing they'll have to settle for a lot more than a DVD.
But really this is a win-win. Alamo will get so much free publicity and public goodwill from dragging this out. Alamo can easily hold some extra screenings to pay for the eventual lawsuit / settlement, which I bet will be very well supported.