I just found it hilarious. Yeah she was rude and blunt as fuck, but apparently she wanted to be extremely clear to this guy I guess. She's never been one to be polite just for the sake of saving feelings either.
One time we were at a bar having some food and a couple drinks, just relaxing after work, and a guy near us struck up a conversation. He was nice enough, but it was clear early on he was trying to figure out if we were "together" which we are not, just friends. At one point he flat out asked if we were together. We said no, and his next sentence, word for word was as follows:
"Well fuck Ariel, you wanna hang out some time or something?"
She simply said "Probably not."
Then he says something like "Wow that's rude, you didn't seem stuck up before but now... shit I'm glad you said no."
I think the normal thing to do is politely make up an excuse why you can't hang out with them "I have a boyfriend" or something like that. But when you're honest and just say no, people really don't take it well.