There's a really easy way to figure this out.
Go to UPS.com, enter the dimensions of a box and the approximate weight, plus the ZIP code from Jeff's facility to your house, and there's an estimated shipping quote.
Priority Overnight service is insanely expensive whether you use UPS or FedEx. I am a hobbyist breeder and have shipped out many fish over the last few years via FedEx Overnight. Adult discus and medium cichlids average about 12 - 15 pounds per box. The last time I shipped overnight from Florida to Connecticut was $120.
There are a lot of vendors who will ship cheaper than that, but I suspect they have negotiated lower rates with FedEx because of the volume of shipments they have. Because I only ship out maybe a dozen boxes a year, this would not apply to me and I have never looked into it.
Remember that your shipping doesn't just depend on the location, but also the size and weight of the order. If you're getting larger fish or fish that require larger bags, that means a larger box, which means UPS/FedEx charge you more. Couple that with the fact that you live almost all the way across the country and $100+ doesn't sound out of the ordinary at all.