It's hardly an illegal advantage when it is the classification given to FedEx by our government, regardless of whether you or I agree with it or how it came about. Your, and UPS/IBT's, opposition to it does not make it illegal. I'm not going to say that our couriers are "pilots", that's just stupid. The difference lies in the fact that the vast majority of Express volume moves by air vs. the majority of UPS volume moving by ground.....this is the key difference. Everyone is too caught up in the whole FedEx couriers do the same job as UPS drivers.....there is a bigger picture here, the company as a whole and how it is structured.
I can honestly say that I have NEVER seen an Express pkg move by Ground or vice-versa, other than the Ground pkgs we pick up in Express dropboxes b/c people can't read/don't care and drop them in there anyway b/c they know we will get it to the Ground driver for them. We have to truck some 2 day/XS freight b/c we don't have room for it on the planes, why in the world would we fly someone's Ground pkg that they paid $10 to send? A few exceptions here being Hawaii and Puerto Rico, which we do have Ground service to from the mainland US.....maybe this is what you have seen.....no other way to get it there in less than a week or so except by ship.
Why wouldn't the Tennessee Senators be on the same side as FedEx.....every Senator's job is to act in the best interests of the state/people that they represent. FedEx is one of, if not the biggest employer in the entire state. It would be career suicide to pass legislation that is not in the best interests of the largest employer in your home state. It doesn't matter if they agree personally with it, their job is to act in such a manner that it represents the majority of their constituents. Assuming their constituents are not made up of the people that work at your station, whom according to you, would mostly vote for a union given the option....they may very well be representing the will of their constituents, regardless of how much you think FedEx may be paying them. I am sure they are getting something, but that's no different than anyone else getting campaign contributions from companies in their home state.
And no, I don't think that all Senators/Congressmen always act in a manner that benefits their constituents......if that was the case, this health care legislation never would have passed, that was due to the President buying their vote in return for funding of their respective pet projects/states........no different than how it works with companies really.