Probably the first time this issue really came to the public's attention was after the release of Windows 95 and the rise of the Web. Famously, Netscape looked poised to make Microsoft irrelevant and make the browser the "new desktop." Microsoft used its control of the OS and its tremendous sway over computer makers to foist its browser on the general public, and changed the course of computing history. If it hadn't gotten in legal trouble, Microsoft might have had de-facto control of the internet by now.
Apple has certainly raised the ire of the geek elite by using its control over the iOS ecosystem to channel users to its own App and Music stores, becoming an immensely rich and powerful intermediary in the process. There's a lot of hand-wringing going on right now as both Apple and Microsoft seem to have similar designs on the PC space.
Of course Apple is also the hero of another story. The main reason why mobile computing was hobbled for years after we had sufficiently advanced technology to make it possible was because of the stranglehold the carriers held over the OSes on their phones. Loaded with crapware and channeling all customization and commerce through their pathetic portals essentially guaranteed there would be no advancement or innovation. It was only Apple's leverage in granting the iPhone to only one carrier that broke the barrier and started to give mobile users control over what their phones can do. The Android ecosystem still suffers, though, as the carriers customize, generally to ill result, their pre-installed OS, and often restrict upgrading or reinstalling Android.
It would be relatively trivial, technologically, for Microsoft or Apple or Google to silently demand a cut of some or all commerce transacted on their platform, as Linux Mint did. Even if it were easily circumvented by those in the know, such a move would be likely to reap huge rewards. Maybe by this point it would be impossible to achieve without serious legal repercussions and of course heaps of bad PR, but it's interesting to think that it could have happened. Maybe the main reason that it didn't was because the internet took both Microsoft and Apple by surprise, and by the time they got on the train, it was too late.
In fact, the internet took everyone by surprise, and it really only exists as a marvelous accident of history. If our political and business leaders had been able to truly imagine its impact, it surely would have been strangled in the crib by attempts to control and monetize it. It's no accident that the chaotic, free version of the internet came to the fore, because all of its non-free, controlled predecessors were indeed killed by the control,short-sightedness, and greed of those that held a little leverage over them. Only a free network that "interprets censorship as damage and routes around it," will continue to grow and thrive.
So for that reason, I think that Linux Mint ought to be chastised, not because this particular example is a big deal, but because an OS vendor interfering between the sites or apps that I'm using and the larger network, whether it's spying on my usage a la CarrierIQ or skimming a piece of ecommerce transactions, ought to be condemned strongly, lest a larger, greedier, and more powerful entity gets the bright idea.