The question now begs whether the benefits of their service warrants the extra cost?
Size of the box is also a very important factor. Using the free USPS boxes, it can be double or even triple the cost of a tight fitting box. Size does matters ;) We currently have 20 different sized boxes in our warehouse.
We are trying to offer an amazing service but still remain competitive to current pricing.
Saying that, there will be a ton of people who will do anything to save a dollar. I value my time very highly and assume a lot of other people do as well.
What would be cool is if you provided the same kind of service that paypal does for shipping (print and prepare labels etc.) as an addon / plugin to shopify or other shopping cart systems.
Check out Ordoro for printing labels. I think they integrate into shopify. Not our business.