Well, I think the reason she sings these songs all the time is because she knows that not all of her fans can make it to every single one of her concerts, and so she sings for her fans who can only make the pilgrimage once in a while, or even once in their lifetime. Fans like me
So I was ecstatic when I heard her open Arena Tour 2007 (my first Ayu concert) with Evolution, and then go on to sing M, Surreal, Unite, Boys & Girls, Who..., some of her best stuff. Hearing M live nearly brought me to tears.
I've discovered that her concerts are really meant for those who can actually attend. It has to be experienced. So much is lost watching it on DVDs