bloke: The campaign revenues are in the 10s so you just have to look it up.
What the industry is lacking right now is a high-end campaign management service. Scanbuy is filling the higher-end role right now, but the next big player will be a full-service, in-house, end-to-end solution with project management and client service groups.
For the most part, campaign managers have all envisioned a solution which is much like NeoSphere and requires the client to log in and manage their own codes. That probably sounded great to software developers and mobile-resumed CEOs, but it doesn't work in the brand and advertising world.
Your numbers are off, and they have fees for than scans, but yes it requires multiple campaigns to be successful. 1M scans a month is very realistic. I come out the big brand world, and we are certainly not interested in creating a campaign with only 1 million impressions (with the average campaign lasting about 4 weeks).
The supply in this case would be the number of companies which can manage a national brand. I would put the number at maybe 3, and that is stretching it.