I've, um, heard, that more sophisticated phone trees react to profanity by connecting you to a person more quickly, using the logic that you sound pretty upset and need help now.
The client really didn't want people sent to live agents if at all possible, as they only had a certain low number of agents and wanted to keep it that way, so we had extra prompts that tried to convince the user to give the app a try first before we did a transfer to an agent, but it was something that could start the process off.
And this was an IVR app for a Fortune 500 corporation, not a small company.