Sure... they could play the "she was a child and didn't know any better" card, but that explanation would be unsatisfying and feel like a cop-out.
That explanation is also on thin ice because she's not a child anymore, yet she still seems to say whatever is on someone elses mind. Despite the fact that she's gone through so many horrible experiences that were a result of her power, it doesn't seem like she's learned anything. She just keeps repeating the same mistakes.
When I say "same mistakes" I'm referring to the class president/tennis club member conversation.
She goes to a new school for the umpteenth time, before doing the same thing that made her leave her other schools and caused her family to abandon her. Bwuh?
I can understand this in a way though, because if she had already learned to cope with her problems, then there wouldn't be much pretext for this anime to work off of. I.E no character development.
Actually, that's a lie.
A girl who has ESP is a great premise to make stories from. Depending on how they created her character and the setting, they could've made her grow in different ways besides making a series about her learning impulse control when it comes to opening her mouth. I think they just picked the easy way out as far as storycrafting goes.
Despite all that I've said, it's still too early to be judging the series this harshly. I'm just gonna keep watching and hope that they answer these questions, or maybe go in a direction that I'm not expecting it to go in.