I sell a little on ebay. I charge typically $5 for shipping.....the usual cost for USPS Priority w/sig. conf. plus 50-75 cents to cover packing supplies. What slays me is those that scream "You didn't pack my item well enough....should have used big-bubble bubble wrap and lots more peanuts." to shippers and yet cry "His shipping charge was higher than what was printed on the shipping label put on by UPS/USPS/FedEx/etc." Heavier items are packed, weighed, calculated for California shipping (the longest distance it can travel from me), calculated on the UPS website, then $1 added for packing materials.
So where are people getting this free shipping materials, hmmmm? Boxes are no problem and never have been......but bubble wrap, peanuts, tape....they all cost money.......especially with wrap and peanuts, especially when packing a heavier item s o it won't shift/become damaged in shipping.
As soon as the packing materials become free, my shipping costs will be the "actual" cost charged by UPS, et al. Until then, my shipping, which is almost always stated in the auction, will attempt to defray the cost to me of packing materials.