It really depends on how far the package is going. I can ship a 4 pound box within my state for under $8.50. USPS is still the cheapest of any carrier. I don't like paying high prices for postage but when you figure what you are getting for that price, it is pretty amazing they can do it without charging even more. It was a real big help to me when they increased the first class package limit from 13 ounces to 1 pound.Yeah but the USPS is outrageous for a pound or more - I really hope President ***** reorganizes the USPS or something because its out of control. I thought I could ship something for about $4 because it was just a photo frame and altogether I think it weighed about 1 pound 2 ounces. Pretty light I thought and only going a couple states away. They wanted $10 for it - then I was like can't you do any better then that? And the best they could do was send it some other way for almost $8 which was still twice what I expected. So that $8.50 Tradesy label makes sense plus they don't take commission out for shipping when you use their label and now that their commission is so high - it really makes a difference. I just have been too busy to change all my listings raising prices and switching over to their labels.
You are paying more by buying your postage at the post office. You have to pay extra for delivery confirmation and the rates might be higher. I buy my postage through paypal for my non-ebay sales and have USPS pick the packages up from my house. My carrier scans the package when he picks it up.