in our solution you will have to use Mikrotik access point(it's a lot stable)
there will be a central server/VPS(Debian x64 os, 1Gb ram, 10Gb hdd, 1Ghz processor)
user will not have to like your facebook but a text will be posted to their wall(this will attract all their follower and will be visible on their dashboard also)
people who don't have facebook will register with mail id
you can set speed limit of user per cafe basis
it will show the number of users
number of male/female
age group
etc info on your dashboard
we will make a simple html design for you(you can get the page designed as per your requirement by any designer)
if all this is ok then please provide me details of your server(static ip and root password)
and access to a Mikrotik access point over logmein and put 100% milestone as bellow
40% server setup and first mikrotik setup done
40% after instruction to setup other mikrotik and you succeed to setup one
20% for bug fix