I think it comes from all three, society, comparison, and personal expectations but society and comparison play a bigger role than most people admit. Once income goes up, the “normal” standard quietly shifts. You see better lifestyles around you, whether online or in real life, and it starts to feel like you should also upgrade things just to keep up or feel like you’re progressing.
Personal expectations add another layer. Sometimes it’s not even pressure from others, but a quiet belief that higher income should automatically mean a better car, nicer home, or more comfort. So spending becomes tied to identity, not just need.