Wow, read 29 pages. Wasn't worth it.
As mickyfu and Sephrata several times mentioned, finding a reliable affiliate network, allowing much traffic from the same ip address, will be very hard.
But shouldn't it be possible to twist this method without a affiliate network? I'm thinking about using a premium sms provider (Short Code Billing / P-SMS). Customers are used to use codes, which they get by SMS, to authenticate for free wifi.
- Rent a premium number, from a premium sms provider and a keyword. E.g. "wifi"
- From the most premium sms provider you get a link for a form, in which the customer has to enter a phone number.
- Implement a link to the form, with a button "Get access to free wifi" or something.
- The form of the premium sms provider want's to show the visitor, that this service will cost something, and the costs will added to his phone bill. Hide all this information. So the visitor is still thinking, the wifi is free and enters his mobile number. To do so, maybe some premium sms provider allow using their forms within iframes, but I dont think so. But it's your network, should be easy to inject some CSS inside the providers form website, which hides the price tags. Sure this will break the secure https connection and the visitor will maybe notice, that the connection isn't no more safe... but hey... free wifi!
- The visitors enters his mobile number
- Visitors get instantly a sms with a code, which the visitor has to enter in the form from the payment provider. (Chose a premium sms provider that does not mention the costs inside this sms. Some providers send only the code in this sms, because they already mentioned the costs on the form which asked for the mobile number)
- Visitor enters the code or gets asked to answer this sms with your chosen keyword.
I think the conversion from visitors could be quite good, because this process is familiar to visitors. At least I know this process from free wifi in trains and big fast food restaurants, with a yellow M.
Wondering if some premium sms provider check their payment forms for injections like this. Maybe it's easier to build a own form, for entering the phone number, already without the price tags, which only hands over the number to the actual form from the payment provider. The same with the form, where the customer should enter the authentication code.
Another twist could be using a WAP billing provider instead of a premium sms provider. It's more comfortable for the visitors. Just an click on a button, and the visitor will be charged. WAP billing also allows subscription. The subscription for a wifi access.
Many visitors won't notice the extra 3,99 EUR/USD or other costs on the monthly bill. Some will complain about the costs, and will ask their telecommunications company, from there the costs come. But unless the visitor has a clew, it is from the wifi you provided, AND joins the wifi again, to make screenshots, evidence of the payment website, without the price tags, there should be no problem.
Because you used a serious premium sms provider, that uses payment websites with clear informations about the costs and the visitors uses the keyword/authentication code. It will look like, the visitors didn't see the price tags, and bought a paid wifi subscription by mistake.
Only some hypothetical thoughts.