Ironically, Willow was upset with Buffy about what she had done.

I don't think Buffy did it for the thrill (like when she robbed in S3 with Faith), I think she had all these girls depending on her, and felt it was necessarily that she had to get them a place to hide filled with weapons and armors to protect them. She felt guilty about it, especially when Willow knew and was upset with her. S8 Buffy is really an interesting continuation of S7 Buffy, who felt disconnected from everyone, doing what Voll had accused her of.