I am. The Skyliner is a limited express train, so the ticket has two components - carriage and seat reservation. The figure you're quoting is the carriage part. The Skyliner is also a 100% reserved seating train, so you have to pay ¥2,470 for the leg from Narita AIrport to Keisei Ueno Station.
I don't think you'll have any luck trying to convince the Keisei staff to sell you the ticket for the same price as Hyperdia.