I think the cost for mailing needs to be looked at overall. I would like to see it established that books have to be shipped at least First Class and Media Mail not be used at all.
I've been under the impression that comics aren't supposed to be sent via Media Mail anyway. I just paid almost $14 to get 4 books shipped (two transactions, my own fault.) and the seller has sent them Media Mail. Kind of bad form, when you think about it.