It's the first one. The episode highlights the importance of money and that sometimes people can do anything to get their hands on them. The kid was thinking that he would only be accepted if he had a huge fortune like the rest of his friends. So he put on a mask and pretended to be rich.
In the end, the parents clearly remembered what happened. Since they got to take a huge amount of money by the end of the episode which made them endure the humiliation, they didn't tell anything to their son about his wrongdoing. For me the episode clearly highlights the huge distance between the poor and the rich and that money basically controls everything, even human dignity. The rich know that they can cover up anything they want, because they have money and they also know that the poor will comply even if they're being wronged, because they are in need for the money.
There is something that you probably missed that basically confirms this. Their kid had told his parents that he was going to go in an excursion with his friends (I think he said that he will go to camping). In the end his parents say something like "if you go to camping again, let us know" which basically means that they are willing to be humiliated and almost killed again just to make more money.
