Your problem here, and I know a year has past, is the result of Kubota's business plan. For the tractors, they strive to set a lower price than John Deere, through spec, setup and Margin. To drive up their sales.
But for the attachments (especially if they know off the bat that you are getting more than one attachment) they jack up the price to offset their margin they lost on the tractor.
Most people price the tractor, and never price the attachments. A good deal is never what it seems. Did you go in there with a price on the John Deere Tractor? If you did, was he lower? I wonder why? Because he knew he was going to get you on the snowblower, so he dropped the price on the tractor.