[Matrixbeast]

So you didn't pick up on Amu breaking down their plans on finding the cube, noticing how handing out flyers won't actually help, and choosing to shop because she would prefer to get accustomed to her new home rather than desperately cling to their old one?
Because the episode where she did it (I don't recall the number) made it pretty damn clear.
I'm not going to break down each and every episode to find traits, I'm looking at the characters as a whole. Amu is extremely observant and clever, and can be down right manipulating, but if you only see "Vapid shopper" in her, then I'm surprised you caught anything in Tusk.

We know Tusk's personality traits, but we don't know Tusk at all. He stands around quietly, acting stoic. Shame Sela did it better and with better reasoning (Her family that she can no longer see). He's observant. Great quality. So are Yamato, Amu, and Sela. He rarely comes up with plans to attack or counter enemies (He only really follows the others' lead), and he's clever, which doesn't serve his character since he's never been in a situation where it would pay off (He didn't figure out a way to save Amu as she already had a plan, and he didn't figure out to attack the hat until spelled out for him).

I'm sorry, but Tusk just doesn't add anything to the team in my eyes. In terms of wit and intelligence, he's probably the smartest, but he's never been in a scenario where he needs to use his wits to defeat a foe or solve a problem. In terms of humor, Sela plays a better straight man to Leo, while Yamato plays it to Amu. He just stands in a corner shaking his head. In terms of ability and battle, Leo is shown to be nearly as strong, but twice as mobile, while he has no particular abilities to help beyond his earthquake stomps, and he just so rarely comes up with battle strategies.

I like Tusk, I really do, but in the big picture, he's easily outdone by his whole team since he rarely gets the chance to shine and his days in the limelight don't play to his favor.