Meetup has done a lot to bolster the tech community in NYC. I have met almost all of my tech friends in NYC via meetups. Meetup employees even come to some of my meetups. I know for a fact that they care about creating positive environments where attendees are not bombarded by commercial interests. They want you to go kayaking with other kayakers, talk about programming with programmers, or find out how to cook fantastic vegan food with other vegans.
False positives sometimes occur and it's a shame. Perhaps meetup could've been more proactive before shutting the group down. I personally feel confident that meetup looked at the group and made a fair decision that it was indeed violating the terms of service.
As I mentioned above, I host three meetups so perhaps I'm biased. Here are they: http://www.meetup.com/hack-and-tell/ - http://www.meetup.com/DUMBO-Tech-Breakfast/ - http://nyc.brubeck.io/
If folks would prefer to use eventbrite, obviously do so. Eventbrite has no community building tools. It is a website for tickets. Meetup, on the other hand, cares so much about building communities that their whole site is built for this purpose. You will lose that.