Do all international airports have WiFi?

How come free WiFi access in airports is so scarce?

• I've been through quite a couple of airports, mostly in Europe, some in US, so far and in general, free access to unlimited WiFi is generally a dream. At best, you get 15-45 min free sessions, either directly, or after surveys and such. If you're lucky, the sessions are MAC based and you can get more, probably against some of the ToS. If not, they ask for some pieces of information to limit access (such as one session per day per phone number). However, I've heard from people travelling to/through Asia that reported unlimited free WiFI with almost no friction... I would have expected at least some of the big airports (Europe: Frankfurt, Heathrow, CDG) to be able and willing to provide this with relative ease, given the number of passengers flying through them each day...Is this somehow economically unfeasible? Is the potential demand too low to be worth it? I'm having trouble understanding why this is not a more high-pri issue...

• Answer:

  Simple as this...free doesn't bring them any money, and in fact it costs the airport money to provide it. I hate that so many airports in the US don't offer free wifi, but think of all the business travellers that are on the road all the time and sign up for "Boingo".  It's clearly a moneymaker. No airport will gain passengers by offering free wifi, at best you might have people linger around more and spend a bit more money, but that's a bit of a stretch.