Mobile telcos have been doing this for years (at least a decade). But let me tell you right now, it's NOWHERE near as bad as it's being made out. Simply because the requirements to get on deck were so onerous, only a few people would bother with it at all.
For webmasters who would like to figure out how to serve/bill stuff to users on mobile websites, you've got to have some way of passing some kind of UID for the user connecting. For magazine/media sites trying to actually run a business, being able to serve stuff to users with the ability and inclination to pay for content was pretty important.
Back in the day before the iPhone (and I believe this was more common in the US than elsewhere), users on web-capable phones issued by carriers would start their browsers, and land on the carrier's home page or "home deck" (think WAP). I remember getting "on deck" (linked off the website at a carrier), was a massive pain in the arse, because you'd have to make sure the website work on their top 10 devices (a nuisance, because Netfront (and the phones it ran on) was a bigger piece of shit than Netscape 4 and IE6 combined), and then after all was said and done, you'd have to give the cellco a huge cut of any revenue you generated.
(Note that I'm limiting the discussion to websites linked off the cellco's front page; not 'off deck' stuff, like those old magazine ads flogging rubbish ringtones off premium rate phone numbers. That's a different story and the billing works a bit differently.)
Naturally, once you managed to get 'on deck', you'd get access to the cellco's billing infrastructure, which'd let you sell subscriptions and flog pay-per-event stuff like wallpapers and ringtones (which, back in the day, a rubbish poly ringtone costing £2.99, was HUGELY lucrative if you sold a few, and made SMSs seem like good value). But only after you managed to make it on deck (otherwise there's no traffic, and thus, no revenue). And then you still had to deal with a completely, utterly different billing interface for each carrier (some using transparent proxies, some using redirects, some using web services, etc). And of course, the dubious pleasure of dealing with the cockheads at the telcos themselves.
Naturally, to keep this going, the cellco would only flip the big switch to pass through your phone number to that particular website in very specific circumstances (like, a tiny number of very well known websites owned by very well-known companies (like Disney)). It's a whitelist -- and a small one. Hardly the scale of threat being implied by the lede.