If you, personally, screw me over, I will use every method at my disposal to get my money back.
If I lose money because I was not thorough enough in evaluating a deal, then that's something I have to learn from.
The difference here is that in the first case, the other party has a clear criminal intent, while in the second case, the deal was legal but I failed to do the research on it or think it through rationally.
EDIT: The thing with microtransactions is that they're definitely legal. There's no false advertising or anything, you generally know exactly what you get before you make the purchase. Whether or not the product you get is worth it is highly subjective.