To me this is the final straw. By contrast Slack's privacy policy mentions they "plan to allow team owners or administrators to enable an optional feature which would allow them to view anything inside their teams".
They add: "When this feature is added, notices will be visible to all members on teams where it is enabled."
Keywords: optional & visible.
That's exactly the kind of thoughtful consideration made obvious when you first use Slack. The product direction on HipChat during the 6/8 months we've been paying customers has been disappointing. Instead of working on in-app history search or the other dozen of clamored for features (http://help.hipchat.com/forums/138883-suggestions-issues/fil...), they pilled on a not really necessary audio/video call feature.
I can only hope the HipChat/Atlassian team considers making admin access to private conversations optional and visible as well.
Your circumstances don't sound like they would be rare.
It'd be nice if you could take a conversation off the record. Is it inconceivable that HipChat may be used for human resource like discussions? I see some risks with this, and not sure I agree.
However, I do understand why they would do this. Bummer.
I truly feel that if the chat platform is being provided by the employer, then they have every right to disallow you from taking conversations offline.
The problem really lies with Atlassian for not offering better permissions.
The new API allows you to request personal tokens or room tokens (you'll need to be a room admin for that).