The problem isn't Facebook. The problem is that the community center decided that maintaining a website wasn't worth the cost and/or the effort.
That was a glib remark, but in all seriousness ... for the average non-technical user, who's friends are all on Facebook, their event and group system is a godsend. Non-FB solutions should realize that and figure out ways to make more accessible (and cheap ... aka free) systems
The world is complicated :)
File a polite complaint that they are excluding members of the community unnecessarily, and that alternatives like meetup.com exist so you don't even need to run your own web server.