I don't know about Fed-X, but UPS has different tiers for their customers. I use UPS here and have close to $8000 worth of shipping charges per year. In the past 5 years, they have REDUCED my shipping rates 3 times because of the quantities. I never did sign up for their $10 per week daily visits. I do have my drivers cell phone and just call him when I need to ship. I have on occassion called the terminal if the driver is a sub, and they would waive the special call fee.
When I spoke to the rep at the terminal about a daily stop and if it would reduce my shipping fees, she told me I was already getting the preferred shipping rate, and that UPS had waived the weekly fee.
When I return a package to the customer, the UPS shipping charges are always cheaper than the UPS charges to a retail customer, by about 15%. Most times, when a package come in from the USPS, the shipping charges are on the "stamp", I can beat them by 20% or more.
I've gotten nothing but great customer service from UPS. Then again, I'm dealing with a small terminal in Bemidji, MN, and is kind of a family run operation.
Doug