Karen, I know what you mean, and I hate the fact that if one says it's ok why would the other one add additional Charges. I get irritated with our local post office, They will smack me with 20 cents on a lot of my blocks coming home.
It is not the fault of the sender it is the fault of the post office's not being consistant. Really bugs me, but being easy going person I am I have a collection of pennies for just that occassion! Normally I am not mean spirited, but giving them pennies is my way of equalling the universe!