Oh they're well within their rights to do that. However my complaint had to do with the fact that one of their higher ranked volunteers was trying to point to an issue with the system after being dismissed and instead of trying to work with their community and address it, they just ban him instead. To quote him:

> For me, it was always like I was looking at a five-alarm fire,” he said. “To them, it was smoldering.

Because he fixed thousands of fake edits that were against the terms of service.