I know this will not happen any time soon - but it would be a great point to get to.
THE PROBLEM:
The Chillispot/Worldspot model is based on tickets being managed off site, but printed 'locally' by some manager person. That is a good model for many cases. It is not a good model for a busy cafe that wants to give QUICK tickets (free or paid) with every coffee/cake.
THE COMPETITION
Netgear (I think) sells a Point of Sale (POS) box that is expensive - but does everything in one place. The seller presses a button on the printer and out comes a ticket. The printer is connected to the AP. This is a good model for Cafe's.
THE DREAM
The WRT has an IP printer connected to one of the LAN ports. Thermal Printer has buttons (A, B, C, D). Staff press 'A', out comes a 30 min ticket, B = 60 min, etc. (A,B,C,D defined in the WRT admin). The ticket comes from WorldSpot. This means more firmware for the WRT and printer of course.