The difference is that NewEgg uses FedEx Super Saver Shipping for their products; it's very considerate to us users. What it means (from what I garnered from the details from the FedEx website) is that they prepay a certain amount based on the type of thing they ship. Even if they were to ship standard FedEx (without Super Saver), they would save at least 30% over UPS (which is what the others use--UPS Ground). UPS has at least been overpriced for a few years now and yet supposedly merchants continue using them. Now, I'm unaware if perhaps UPS gives the merchants a nice discounted shipping, then they charge us consumers more than they pay... Either way, the way to go about it is demand each retailer that uses only UPS Ground to start offering FedEx, so both they and we can save the 30%. I once complained to Meritline.com with the same thing (blasted $9.39 shipping for one 100 spindle that would have cost $4 at NewEgg) AND I gave them the lowest rating possible at Bizrate.com b/c of lack of shipping options/prices. They sent me a $4 credit, although I would have preferred them switching to FedEx (which also delivers on SATURDAY, whereas UPS shuts down on Friday afternoons). So, another way to pressure them (it's your right as a paying customer) is to ask to rate them (check the box on your order, so you'll receive one to fill out by email) and give them the lowest rating possible under all the corresponds to shipping. Then, if there's a 'reason' box for why you did so, put something like "should use FedEx, as it would save us at least 30% on shipping cost, instead of forcing us to pay for overpriced UPS Ground shipping."
In the end, it's just lazy and stupid to not switch to a just-as-reliable service from FedEx that also ships packages on Saturdays AND is lower cost for all involved. The only explanation is that UPS gives the merchant a better deal on shipping than we get--but then we as consumers get charged more regardless. So, unless we all demand better, we won't get "better" from these guys. If a bunch of CDFreaks members do this, these do-dos will get the message and start using FedEx.