@kaputnik, a while ago I've seen a photo of a draft beer tap installed on a Ute deck, with kegs presumably in the bag. Can't find the image now, but did find this:
Various beer and/or children carrying photos here (not at the same time, obviously):
http://www.flickriver.com/photos/tags/snapdeck/interesting/
@DaveC, yeah I know, but the seller has it seems sold carbon fibre racing bikes the same way with positive feedback and comments, so we'll see. Cameraphone at the ready as I unpack, methinks!
You are thinking along the same lines as me re: clamping a seat on. Ideally I would rig something so I can take the seat on and off quickly. As wingpig notes, the width of the deck may preclude using some kiddy seats. I love the home made wooden affairs I've seen on Flickr and so on, but not sure my carpentry skills are up to that!
This Ute owner has an 'official' and quite functionally elegant solution in the Xtracycle Ute deck (with pre-drilled holes) but really if I wanted a black plastic deck I'd have got a Yuba Mundo or something...
I'm looking at some foam rubber, a waterproof fabric cover and some strong elastic to rig an easily removable pillion passenger/stoker seat for the deck. A bit like this.
More Ute love-in pics:
http://www.flickriver.com/search/kona+ute+/