When we were using charts (and perhaps some offices still do) there was a greater possibility for errors to be made. Now, with the Point of Sale equipment the pricing is pretty much cut and dried, assuming the right zip code is entered.
In some cases, you can save $10 to $15 on shipping by going surface as long as you don't get stuck with non- machineable or the "balloon charge". It does take a few days longer, but may be worth it.
I recently mailed a couple of bows. I much prefer to add extra support to the cartons versus having the hassle of filing insurance claims. Yeh, it cost me $36 for priority and insurance. Perhaps agreeing for both shipper and receiver sharing shipping costs would be more equitable .