Well, yeah, I know about that...maybe it's just the combination of showing his teeth with his hand on his hip while doing the peace sign. It feels very 'Japanese'.
I mean, compare that 'very humble' looking Rareware render to his 'Ultimate Pose'.
Edit: I meant to say "It feels very 'Genki', not 'Japanese'. Banjo is posing like a anime school girl than as a hillbilly.