Shouldn't First pick get the bans?
Odd question...
But, first pick puts you out in a very vulnerable position where you are likely to be countered if your opposing laner happens to have your counter in their champion pool.
Wouldn't it make more sense for the person forced into this awkward situation to have the ability to at least blackball one thing? That one hard, devastating counter?
The people last in the pick order aren't likely to get counter picked since there's no-one left to respond to their pick.