I am very sorry you had this type of experience with the walk around's. (What area were you in when it was said to you and your friend?)
Just so you know our walk around talent gets verbally harassed by Guests all night, so its very easy for them to get mad and rude at park guest right back at even the slightest remark. Its not your fault at all, but they are people just like you and me, and trust me when I say that after a long night of dealing with teenagers, Its very easy to be rude to everyone.
And yes the guards are just they're to make sure that guest aren't assaulting the ghouls, they won't do anything else.
Again I am sorry you had this experience and visit the park again soon.
Thanks, We took it up with Six Flags and Some managers are looking into it. But we didn't even do anything to the "Talent" we were just walking around and one of them tried to scare my friend and they had a stare off and then he started with the insults. But they were all laughing about it once we walked away.