Ariana Grande and Chris Evans did not realize that they were playing a cruel parody of themselves
They probably thought they were making fun of someone like Paris Hilton. While actually filming a mocking parody of themselves. Because that's how they behave and that's how normal people see them.
It's amazing how the director managed to lure them into this. Well, celebrities aren't very smart, so it's no surprise they didn't get it. I wonder if anyone in their circle told them.