First of all, its not a theory. Its just a metaphor.
But let's try and speculate how people would find a way to complain about being given $100 in each pack. Imagine for a second if Blizzard does a promotion where they send you $100 for each pack bought in a certain time frame. Lets try to theorycraft the things people will bitch about:
It seems likely that the servers will explode and a lot of people will not be able to cash in on as many packs as they anticipated so there will be a post on the front page complaining about this.
Someone will point out how the maximum Battle.net balance is $350 so this promotion is unfair to people without bank accounts who buy physical gift cards by capping them out at that amount.
Assuming this promotion is limited to a certain pack, someone will buy the wrong packs and whine about it.
The bitching about conversion rates will be reignited.
That's just what I could speculate as plausible whining posts, but I'm sure there would be much more.