User blog comment:Blackendedsoul/Bounty List/@comment-3213092-20110412101123/@comment-3425840-20110412124854

Apparently Kaido has much more ferocity than Shanks, just like Kid had a bounty more than Luffy until the time skip, his bounty should be higher than Shanks. As for Big Mam, she seemed to me like a person who is more into flashy things (just a hunch) and thus has a higher bounty.