Don't take it personally. You probably took their chips which prompted them to lash out. It's part of online poker, not just the PokerOwned freerolls. I've only been on the site for like 2 months and most of the people here are really good people. There are only a few I've seen who really like to talk down to everyone.

So you can report it to Carbon, and if they're found to have been abusive they might have their chat privileges revoked. i've just learned to ignore people who talk shit since responding to them only validates their aggression and gives them what they wanted out of it. If it gets too annoying I'll just block them. But don't think everyone is like that. In my experience the freerolls here tend to have a much friendlier crowd than the general tourneys.