Where has the respect for time gone?

I don't understand why people can't grasp the concept of time these days. I mean, a party is set at 4pm and yet one can book tickets at 3pm. I just think it's about respecting other people's schedules as well. Unless it's an invite that can't be turned down, or work. Such actions reflect that one finds it a prerogative to be late. Maybe I'm anal and exceptional, but I definitely wouldn't wish this on me if I'm the host. And yes, saying something like this in a group chat becomes a conversation killer and party pooper. But I simply can't comprehend. I think everyone should have respect for other people's time.