TomS2 - 2:34 am on Aug 29, 2010 (gmt 0)
Hmm. Never had THAT issue with USPS. If I buy postage online, I just drop it in the box and away it goes. Usually it's Flat Rate Box stuff, although there have been a few standard Priority Mail or Media Mail items that I've sent using on-line postage, and never an issue with Postage Due - I did notice that regardless of what I get charged, though, the amount SHOWN on the label would be the amount I'd have paid if I went to the window for service.
As To UPS and their packaging requirements - I've never had a claim because of damaged goods in shipment when packed as I described above. Perhaps it's a local issue? Are you sending via UPS, either pickup or at the Customer Service Center? Or are you going to the UPS Store - AKA Mailboxes, Etc.? Those are franchises, and could well be different than UPS Corporate locations.