I haven't seen this happen at all on the forums, but maybe I'm missing the posts. The only time I've ever posted regarding tester status, is in the application thread where people whine or question why they were/weren't chosen, speculating as to the reason us testers were "unfairly picked over them" to which I respond, it's clear that none of us know why we were picked, as the team is very mixed in experience/age/activity levels, so speculating doesn't do much good.
I haven't seen one tester act as though they're staff or have control over anyone else, as we aren't even remotely like staff or moderators. What we do on the other server has nothing to do with other players, or the forums. We find bugs that hopefully help in-game experience. Other than that, we effect nothing. The only "rudeness" I've seen go back and fourth about testers is people in-game complaining because it isn't fair and we were given status, which I find to be silly, because we technically don't have any special privileges other players don't - our ability to spawn items and utilize the other server isn't for fun, as we are not supposed to use that server for anything other than testing bugs and making reports.
I'd have much preferred our "status" as testers to have been kept completely private, as it would eliminate any and all squabbles over the decisions.