Just to take this a little further, with all the 'new' front-ends bolting onto the blockchain, there are no guarantees people won't just be posting MEME's or photos or whatever.
And we can't expect them to stick to the Steemit rules of long meaning posts because some might have never heard of Steemit.
Therefore, controlling this bandwidth allocation is the only way we can control the user experience for all Steemians.
And personally, I only experience bandwidth issues immediately after a payout, and even so, it only takes a few minutes to replenish my allowance.