Or, as we say in English, "what's the big idea?", "what's the meaning of this?", "what the hell do you think you're doing?"
The speaker isn't really inquiring as to the specific meaning of the action. The speaker is expressing surprise, incredulity, alarm, at the action of the perpetrator. Similarly, in the Japanese expressions you have pointed out here the speaker isn't expecting an explanation so much as the speaker is expressing some surprise and frustration at the actions and attitudes of the other person.
We brought you all the way to Disneyland for chrissakes, what do you mean you're not having any fun?
You've been following us for the last three blocks. What's the big idea?
The above aren't meant to be translations of the Japanese sentences you provided, but maybe they will help you see the Japanese expressions in a different light.