No significant effect on the trial is what I mean. Why would the jury members - technically "lay judges", sitting along with professional judges - have taken any particular notice of that kind of stuff, when they could see the defendants in court every day?

"The six jurors – Angeletti and five women – were selected using more demanding educational criteria than those at Knox's and Sollecito's first trial. The lay judges for the appeal had to have spent 13 years at school and obtained a high school diploma. Angeletti said he had heard appeals in four other murder trials." (from here).

Why would the parents do all they could to get their daughter's side of things presented as favourably as they could? Because they were her parents, and they believed she was innocent, I imagine. Wouldn't anyone do that in that situation? That doesn't mean they were spending the money too sensibly.