It's ironic because Brutus really is being drawn into an argument. If Gladys' mouth was open a bit more then I'm pretty sure a second mouth would come out like that alien from Alien.
I assume Brutus has health insurance from the Veeblefester Corporation. It's probably really crappy health insurance I guess which is why Brutus is haggling with the doctor over the cost of whatever procedure Brutus is having done.
