The bullies and their parents were embarrassed to stay longer at the party, so after the commotion in the entertainment room ended, they excused themselves and went home.
The party was still ongoing as not everyone brought their child and not all kids were involved in the bullying. Seeing that Ethan and Ashton had joined them, some of the guests approached Ashton and Ethan to make small talk and curry favor with them.
Even though these neighborhoods cater to those in the upper class, not everyone that lives in The Grandeur came to Phoenix's moving-in party. Those who were in the higher hierarchy didn't care about unknown people's parties. Thus, all these people who were here, even though, may have come from the upper class, but they were in the lower hierarchy. They still need to be respected towards those that were way above them in society.