Well it's hard to recognize these things if you don't have a back ground in Public Relations and Marketing. But here's a simple thought experiment. How many points along the chain would have to fail for this 'accident' to happen? That is how many people/depts would have had to utterly fail at their job.
If it's more than one, chances are it's not an accident.
The Web Development, The Database Administration, The Quality Control and the Management would have had to fail for this accident to happen. Seriously do you know how much testing, double-checking and rechecking goes into the implementation of any transaction system or store front before it goes live? This is somewhere along the lines of a bank teller accidentally handing you a $100 instead of a $10. It can genuinely happen buuut..yeah, chances are it's not gonna.
And yes, I have actually been a part of such 'under the radar' marketing campaigns. Heck they may have already intended to do a give away (GoG gives away quite a few freebies in general). So how hard is it to spin the free giveaway in such a way to make it sound like 'oops we made a mistake! You totally weren't supposed to get or fabulous product for free. oh My. But you can keep them because we be cool like that'
The first one makes customers a happy. The Second one makes them feel lucky and happ, maybe also a wee bit special.
