I feel like this is going in circles. The quote doesn't explicitly say, "None of the following reasons for staying apply, and you have no obligation to stay", it is letting you imagine the myriad reasons you might hang out longer than you want out of some sense of obligation.
If it is really unimaginable to you that someone would not leave a social event the minute they're bored, this whole concept of groups might be a little alien to you. Maybe you're autistic, in a way that's very different from how I am. I don't know at all; I don't know you. But I can say confidently that it is normal behavior to hang out a little longer than you really want to at a social event.
If it is really unimaginable to you that someone would not leave a social event the minute they're bored, this whole concept of groups might be a little alien to you. Maybe you're autistic, in a way that's very different from how I am. I don't know at all; I don't know you. But I can say confidently that it is normal behavior to hang out a little longer than you really want to at a social event.