PrincessBuffy16
Scooby
I think the big difference with Angel taking off was that first of all, he was an "adult" so if up and decides to leave, he has the right. Second, Wes and all of them knew where he was and why he was there. Buffy was a minor and even though she is the slayer, legally she had no right to run away from home without her mother's permission. And the big thing was that by Anne, everyone assumed Buffy ran away and would be found when she wanted to be but before that, they didn't even know if she was dead or alive. She was just gone.
And I totally get that she is the slayer and no one could truly empathize with what she was going through, running away was fundementally selfish. Again, it's not as if I didn't have any sympathy for her, what she must have felt like must have been so difficult to deal with. And to want some time alone to cope is understandable, but to completely up and leave without any consideration for her friends and how they would react is still her focusing only on her pain and not how her friends must have felt as well.
So again, I sympathize with Buffy, but ultimately, I think Xander, Joyce etc. had a right to lay into her the way they did.
Legally, she shouldn't run away, emotionally, she had every right.
I don't think they did. I think Xander reacted the way he did because she ran away because of Angel, not because she ran away. Joyce had that right, because Buffy is her daughter, and like you said, she was the minor at the time, but she never had the right to blame Giles for Buffy running away.